title: Scotch 4 Knights with 4... d5

text:
# Question
Title: Scotch 4 Knights with 4... d5
```
[FEN "r1bqkb1r/ppp2ppp/2n2n2/3pp3/3PP3/2N2N2/PPP2PPP/R1BQKB1R w KQkq - 4 5"]

```

If Black "mirrors" White's move 4. d4 in the Scotch 4 Knights, and White wants to play sharp, aggressive moves, what would be the best move? I know that chess engines like Atockfish, GNU Chess etc. would calculate the next move forWhite as Bb5, but I want to exchange pieces. So what would the strongest capture be here?

# Answer
According to 365chess.com's opening explorer, 5. exd5 is the best capture, with an 83.3% win rate.
> 1 votes

# Answer
`4...d5` is really bad, if nothing else it leads to at least a clear pawn up for white in various lines that can ensue and they all involve frequent trades as well (as you desired), here are a few options starting from `Nxe5` (a choice well in line with your preferences) leaning on more aggression/direct play and less positional compared to some of the other choices (like your suggested move):

```
 [fen "r1bqkb1r/ppp2ppp/2n2n2/3pp3/3PP3/2N2N2/PPP2PPP/R1BQKB1R w KQkq - 0 5"]
 [title "5. Nxe5"]

 5. Nxe5 Nxe4 (5... dxe4 6. Bb5 Bd7 7. Nxd7 Qxd7 8. d5 a6 9. dxc6 Qxd1+ 10. Kxd1 O-O-O+ 11. Ke2 axb5 12. cxb7+ Kxb7 13. Nxb5) 6. Qh5 Be6 (6... Nxe5 7. Qxe5+ Be6 8. Nxe4 dxe4 9. Qxe4) 7. Bb5 Nxc3 8. bxc3 g6 9. Nxg6 fxg6 10. Qe5 Rg8 11. Qxe6+ Qe7 12. Qxe7+ Bxe7 13. O-O

```

**Note:** Bear in mind that by intentionally opting for lines such as above where you favour trades and direct aggression, you'd be naturally walking into highly tactical positions, so be prepared to calculate many many relevant lines at each point (specially in the given examples above).
> 1 votes

---
Tags: opening, analysis, four-knights
---


title: FIDE World Champions after 1993

text:
# Question
Title: FIDE World Champions after 1993
Are FIDE World Champions after the 1993 Kasparov-Short match, i.e. Khalifman, Ponomariov, Kasymdžanov, Topalov, (not counting Karpov and Anand, for obvious reasons) to be considered actual World Champions, or not? I think that the real World Champions after Kasparov are Kramnik (who beat Kasparov), then Anand, and of course Carlsen. What's the chess world's view on this?

# Answer
> 2 votes
The answer is that both the FIDE world champions and the PCA world champions were world champions.

The situation was actually less chaotic than the normal situation in boxing. In boxing there are four bodies awarding world champion titles. They are -

* WBA - World Boxing Association
* WBC - World Boxing Council
* IBF - International Boxing Federation
* WBO - World Boxing Organization

In the heavyweight division the British fighter, Anthony Joshua, holds three of the four titles (WBA, IBF, WBO) but in the light heavyweight division four different boxers hold the four titles -

* WBA - Dmitry Bivol
* WBC - Oleksandr Gvozdyk
* IBF - Artur Beterbiev
* WBO - Sergey Kovalev

If boxers are clever enough to get their heads round having up to four different world champions in one weight division then I'm sure chess players are clever enough to manage just two for the short period of time of the existence of the PCA.

---
Tags: fide, world-championship
---


# Question
Title: Stockfish: How to do so it only gives hints to one color
When using Stockfish it gives options/hints for both white and black. How do I make it so it only shows hints of moves for black? I am using mac.

# Answer
I assume you want this so that you can train against the engine by playing the suggestion for black and then thinking about what to play as white?

Lichess allows this on their website. Set up a position in the board editor or analysis board, then pick "Practice against computer". If you like, it will even evaluate your moves as you go, telling you if you made a mistake, blunder, a good move but not the strongest move etc.

I often do this because too often I reach a winning position and then go on to squander my advantage. I go back to the winning position and see how to actually convert it.
> 2 votes

# Answer
Just use Stockfish within a database program and pick the "play against engine" option.
> 1 votes

---
Tags: stockfish, macos
---


title: Piece down vs rook for bishop exchange

text:
# Question
Title: Piece down vs rook for bishop exchange
I was recently in a situation in which my bishop was pinned with my queen behind it and my only options were \- losing the bishop. \- defending with the rook which would allow an exchange of my rook for his bishop.

I know both cases are bad but, which one would be worse, or should I say less bad? It could maybe depend on the position as well but I'm looking for an "in general" kind of answer.

Thank you.

# Answer
It's more than just a pawn difference (as stated in other answers). Being an exchange down, you'd still have a minor piece playing against the rook. This is not always a disadvantage, as a knight with a good outpost or a bishop with good diagonals actually value as much as a rook. Your knight could still potentially fork your opponent's queen and king, your bishop could also potentially pin your opponent's queen. Your opponent would still need to prove the exchange advantage to win.

However, being a piece down you would have less chance to come back in the game. Generally, you should not hesitate to give up your exchange to save a piece.
> 3 votes

# Answer
In general, it is better to be an exchange (rook vs. minor piece) down than a minor piece. If you look at the standard table for piece value, you see that being an exchange down is only 5-3 = 2 points, while being a minor piece down is 3 points.
> 3 votes

# Answer
An Exchange (rook for minor piece) is probably worth less than 2 pawns, while a piece averages over 3 pawns. Petrosian once said that the exchange is worth only one pawn.

If you are interested, you could read more about this (and other material imbalances) at this page.

Also, Andrew Soltis' book "Rethinking the chess pieces" is definitely worth a read.
> 2 votes

# Answer
Just a factual observation: many endgames rook + pawns vs. minor piece + pawns are drawn if there aren't too many pawns left and they all are on the same side of the board.

A general minor piece + pawns vs pawns or 2 minor pieces + pawns vs minor piece + pawns is always won for the stronger side (there are some exceptional situations where the weaker side draws, but these may be considered "pathological", and usually easily avoided if the advantage of a piece comes from the middlegame)
> 0 votes

---
Tags: exchange
---


title: Need help with study plan

text:
# Question
Title: Need help with study plan
I am 1700-ish player and have too much time to play, and I didn't choose a study plan. I searched on the web about it, but no one has clearly defined study plan except chess.com and their study plan is trash. I wanted for a help from someone better or same rating like me.

# Answer
> 4 votes
In order to develop a study plan you'd basically have to figure out your strengths/weaknesses and formulate a goal that you want to achieve.

In practice this means that a stronger player would have to analyze your games, but also (particularly at higher level) look at other things such as psychological factors, fitness, etc.

Ideally that coach would spend lots of chess time with you, so being somebody from your area would be preferable to having a random guy from the internet.

Unless you have money to burn or are super serious, IMO the most reasonable would be (if possible) to find a friendly chess club in your area with strong enough players. In my experience players in a club are usually very willing to give advise or tips to improve.

If you are objective enough, you could also try to figure out what you should train for yourself, however at a rating of 1700 that would be difficult to do. In any case you should always analyze your own games to improve and learn what to focus on next.

Once you know what to train for, there is plenty of information on this and other websites concerning improving in a particular area of chess.

---
Tags: study, planning
---


# Question
Title: Is the notion of an en passant redundant?
The en passant move can be utilised when a pawn is offered the option of being able to capture an adjacent file’s pawn, which has advanced two ranks. However, surely the game of chess would be fine enough with the absence of the en passant rule? Yes, it does indeed help locked up pawn structures to not occur, but I do not entirely understand the genuine purpose of the en passant.

# Answer
> 2 votes
If nothing else, it does help to make similar looking pawn structures, behave similarly independent on which row they occur.

For instance *with* en-passant: white: pawn h5, black pawns on h6, g7 would be somewhat equal to the position where white: pawn on h4, black pawns on h5, g6.

*Without* en-passant however black would be able to achieve a protected passed pawn (often a huge advantage in many endgames) in the first situation by simply playing g7-g5 without being in danger of being captured.

Thus not having en-passant would change the evaluation of many endgames and complicate rules somewhat because now you'd have to consider on what row the pawns are as well.

---
Tags: rules, en-passant
---


# Question
Title: Is learning the English Opening helpful for learning the Sicilian Defence? How about vice versa?
Is learning the opening 1. c4 e5 as white helpful in learning the opening 1. e4 c5? How about vice versa?

Are the ideas behind the Sicilian Defence as black very similar to the ideas behind the English Opening as white?

# Answer
> 3 votes
I'd say learning the Sicilian is great for playing the English. Ideas from the Closed Sicilian, King's Indian attack and many others appear all the time in the English with reversed colors.

However, I don't think it works the other way around, as the main lines in the Sicilian come form the opened variation, where the extra tempo is often critical and therefore the ideas played change way too much.

# Answer
> 2 votes
**Short answer: not too much**

\[disclaimer: The more openings you know the more basic understanding of chess you have -- in which case the answer would be "yes it helps you"\]

**Long answer: similar ideas but very different concrete variations**

You would think that because of the similar pawn structures the English and Sicilian sometimes share, that knowledge in one would assist learning the other. In practice though the concrete lines are completely different.

Sure some ideas are the same like in a closed Sicilian Black wants to play b5-b4 and in the English White does b4-b5; that certainly helps. But open Sicilian is a sharp fight and the English equivalent structure results in very different play.

I would say the majority of answers to the English are nothing like the Sicilian defense so if you are thinking to save time by tackling learning these at the same time I don't think you will have much luck.

# Answer
> 2 votes
This is quite a deep question that could be the subject of an interesting book. Without trying to go into depth, I think the main difference is that in the open Sicilian, White often feels encouraged by the non-developing nature of ..c5 to start a fierce attack with Nf3 and d4. In some lines (eg Najdorf) Black even provokes this, believing that it will misfire.

After the English sequence 1. c4 e5 if Black tries to mount an attack the lack of a tempo means that the attack is less likely to succeed, and more likely to misfire, so Black frequently avoids sharp play and plays more on the lines of the closed Sicilian with .. Nc6 and either ..Bb4 or ..Bg7. What this means is that knowledge from the English can be useful in the Sicilian and vice versa, but only if the lines correspond and the players motivations also correspond. This happens less often than you might expect.

# Answer
> 1 votes
Somewhat helpful but for the most part no. The fact that White gets an extra move in the English causes the types of positions to vary significantly. Mainly because Black is more hesitant to engage in the sharper systems being a tempo down.

# Answer
> 0 votes
Sir, preferably English opening may improve Sicilian Dragon and vice versa as both will have finachetto of Bishop with almost similar move orders from both colors.

---
Tags: opening, theory, sicilian-defense, english-opening
---


title: Studying Lost Positions

text:
# Question
Title: Studying Lost Positions
I like to study my games after I've played them. Often, I find myself identifying mistakes and moving on to play another game or study something else. I was wondering if it is worthwhile to continue studying your games beyond the point where the position becomes lost. I'm not talking about extremely lost positions where checkmate is imminent and inevitable, but rather about positions where you are down a minor piece or two and might have a chance at throwing a wrench in your opponents plans and inducing a mistake. It feels like this is a particularly difficult part of the game to study because often times complicating things for your opponent might involve an unsound, but threatening move, something like a bluff in poker. I was hoping some people might have some insights on whether or not it is worth it to study lost positions and how to do so if so. For reference, I am an amateur player who has been playing casually for a few years now.

# Answer
Yes, these positions can be very rewarding. Sometimes, in endgames, there are stalemate possibilities. In middlegames and even endgames there can be tactical possibilities.

If you are far enough behind in material that a standard approach by your opponent of just swapping pieces is going to yield a straightforward win you need to be inventive to make him work for the victory. You can do this by playing actively and aggressively rather than defensively covering up. Make threats. That way you can sometimes create tactical opportunities to get back in the game.

In endgames there are also positions where the player with the material advantage can not win. Queen against rook and pawn can sometimes not win if the weaker side can set up the correct fortress. Sometimes a queen is not enough against a 7th rank pawn if it is on a rook or bishop file with the king next to it. Learn your endgames and look out for these opportunities in your games both when you are losing the endgame and also when you are winning to make sure you don't let your opponent escape.

Even when you appear completely lost there may be chances to trick an opponent who is playing on autopilot. Make him keep thinking and working for the win!
> 3 votes

# Answer
A useful piece of advice is to use those types of positions to practice your technique. Swaps sides, and play against a strong engine. Try a different plan than your opponent used. For example, if they won with a mating attack, try simplifying and promoting a pawn.
> 1 votes

# Answer
Don't forget how how psychologically demoralizing it can be when your opponent doesn't resign when they're "supposed" to. It can be worth studying how the quality of one's game changes after one has broken through after a lot of effort and captured that crucial piece, only to have the reward of the win delayed by a pest who is wasting your time by having the audacity to keep going. When losing badly, you win the right to play like a crazy person.
> 1 votes

# Answer
Generally speaking I'd say no -- two pieces down is just too much, there shouldn't be much potential for play left. In the game you'd be better off resigning.

Or is that too easy? If you had the side with the two extra pieces against a really good opponent, would that opponent find ways to put up resistance?

Nowadays there is a way to check that: setup the position with an engine, let it play the weak side, and demonstrate that you can win against it. If you can, then you were right to stop analyzing. If you can't, try to understand how it managed to put up resistance, and analyze your game a bit further to see if you could have done something similar. Then repeat until you beat the engine from the winning side.

And that a try to complicate things might be unsound isn't that relevant anymore if you're already lost.
> 0 votes

# Answer
You could but I've never found much use it in. The most important part to study are your main mistakes that lead to a losing position in the first place.
> 0 votes

---
Tags: study, losing
---


title: Stockfish 9 giving erroneous reading

text:
# Question
Title: Stockfish 9 giving erroneous reading
Sam Loyd, 1860

```
[fen "8/8/8/8/B6n/7p/6k1/4K3 w - - 0 1"]

1.Bd7!! h2 2.Bc6 Kg1 3.Bh1!! Kxh1 4.Kf2.

```

(Ke1, Ba4; Kg2, Nh4, h3) says mate in 54 after 1.Bd7!! h2 2.Bc6 Kg1 3.Bh1!! Kxh1 4.Kf2.

This is a textbook draw, as the king is on the same square as the knight (with Black to move). For example, in some moment 1...Nf4+ 2.Kf1 Ng3+ 3.Kf2 Ne2 4.Kf1. (No. 205, BCE. Fine.)

Mate in 54? What's up with that?

# Answer
Stockfish 10 of lichess @ depth 74 says it's draw. Only if you can give more details about the version of Stockfish you used
> 4 votes

# Answer
Mmm that's not mate in 54, just a -52.40 evaluation (equivalent of being "52.4 pawns" down).

The engine is calculating far ahead and can't find a forced win, but sees Black's up a pawn and knight so it evaluates based off that. I'm surprised the engine wasn't smart enough to evaluate as a draw though, especially if you're using current Stockfish?
> 2 votes

---
Tags: stockfish
---


# Question
Title: Is the exchange of a rook for two minor pieces really worth it?
I recently played a game with my friend I wish I had memorized the entire game, but, unfortunately, my memory isn’t too good.

In summary, I was in a really tight position, and playing as black. I had a very active rook on the open f-file However my opponent was attacking my king. and it looked really bad. As a result, I sacrificed my very active rook for a bishop and a knight. I still lost the game, however.

Is that kind of exchange worth it? Once I lost my rook, my opponent was able to monopolize on the f-file by making a triple battery, and consequently I lost.

Also, when is it a good idea to make sacrifices concerning Rooks and minor pieces?

# Answer
Two minor pieces are generally stronger than a rook, with the advantage becoming more evident when the game heads to the endgame.

It is clear that there can be exceptions even in an endgame, like one of the two minor pieces being misplaced (a "bad bishop" may lead to such a situation) or a situation where the two minor pieces are temporary unable to parry some direct threat, like the rook being able to capture a few pawns before the two minor pieces have the time to regroup.

While the game is still in the middlegame situations can be very fluid and depend on many independent variables: open files, pawn structures and so on. In any event it is impossible--and unwise--to generalize from one single game or position.

It is likewise difficult to suggest when is convenient to give up a Rook for lesser material. That's more so for the possibly more classical of all middlegame sacrifices: the sacrifice of the exchange. Under the right circumstances a well placed bishop or even a well placed knight may be worth, dinamically speaking, a rook and may give their side a lot of compensation for the material loss.

Yet, one has to consider that average-goodish players do not often have the necessary technique to turn these dinamic advantages into more concrete and lasting ones, so they have to be considered temporary and the learning chessplayer needs to be extra-careful about exchange sacrifices because even if they are good in an abstract "ideal" sense, they might turn out to be poor choices.
> 2 votes

# Answer
You say your opponent had a strong attack against your king and you had to "sacrifice" your rook for two minor pieces and went on to lose. I think you have it the wrong way round. It sounds like your opponent had a strong attack against your king and sacrificed two minor pieces for your rook, your one active piece by the sound of it.

In general a rook and a pawn are roughly equivalent to two minor pieces. However in the middlegame this is usually not a good trade for the player losing the two minor pieces because two minor pieces are two pieces which can attack/defend whereas one rook is only one piece which can attack/defend and the number of pieces participating in the attack or defence is generally more significant than their precise power.
> 9 votes

# Answer
Your experience doesn't speak too much to the general question. Your opponent apparently was more skilled than you, which means several things. First, they probably would have won if you hadn't traded. Second, part of dominating a game is making it so that all of the options available to their opponent are bad; thus, it's likely that they deliberately created a situation where the trade was good for them. Third, if they're a good player, then there's lots of times that they don't make the trade because it's not good. The fact that it worked out for them doesn't mean that the trade in general is good, it just means that it was good in this situation, so there's a selection bias, in that good players select the trade that's good in that particular situation.

The value of a piece lies not just in what piece it is, but where it fits into the game as a whole. If you spent a lot of resources developing your rook, leaving your other pieces undeveloped, then trading minor pieces for your one active piece could very well be a good trade.
> 3 votes

# Answer
The generally accepted numerical value of those chess pieces are that the rook is worth 5 and the knight is worth 3 (the bishop is also worth 3 and the pawn is worth 1). Looking at the situation numerically, losing two minor pieces is -6 whereas losing a rook is -5, so apparently losing a rook would be the more favorable situation and it would seem favorable for you. However, you say that your rook was very active and its loss may have even cost you the game. In this case, eating the two minor pieces wouldn't be worth it for you (the difference is negligible between the two situations, after all, since the difference is just 1, or a pawn, *and* your key piece is gone).

Sacrifice your rook when it sets you up for a good play, be it to pressure the opposing king or to take away a lot of valuable pieces from your opponent, IF the rook isn't your centerpiece to your attack at that moment. If the game is mostly on one side and you've got your rook on the other side relatively inactive, sacrifice it, if need be (don't sacrifice it if you don't need to). The same goes for minor pieces but those are more expendable. It's up to you to evaluate the situation and what you really need, and what you don't.
> 2 votes

# Answer
It's usually a very good trade to get two pieces for a rook. Maybe in the particular game you played it was important to keep the rook on in order to control the file, but in general the two pieces are far preferable.
> 1 votes

---
Tags: rooks, sacrifice, minor-pieces, exchange
---


# Question
Title: What is the longest possible series of consecutive captures?
What is this the longest possible series of consecutive captures in a legal position? Here is an example of 25 on the same square, which is not required.

```
[FEN "q1kr2q1/1qnqnb2/2prp3/q2pK3/2P1P3/1QNQNB2/Q2R2Q1/3R3Q w - - 0 1"]

1. exd5 cxd5 2. cxd5 exd5 3. Bxd5 Qaxd5+ 4. Ncxd5 Rxd5+ 5. Nxd5 Nexd5 6. Qdxd5 Nxd5 7. Qbxd5 Qdxd5+ 8. Rxd5 Qxd5+ 9. Qaxd5 Bxd5 10. Rxd5 Qaxd5+ 11. Qxd5 Qxd5+ 12. Qxd5 Rxd5+ 13. Kxd5

```

# Answer
> 6 votes
Here's an example of 30 successive captures (White's 3rd to Black's 17th). It is the solution (from White's 3rd onwards) of a massacre proof-game found by Gerd Wilts & Norbert Geissler.

```
[Title "Gerd Wilts & Norbert Geissler.PDB CD-ROM 1998-Version"]
[StartPly "4"]
[fen "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1"]

1.d3 d6 2. Bg5 Bg4 3. Bxe7 Bxe2 4. Bxd6 Bxf1 5. Bxc7 Qxd3 6. Bxb8 Qxc2 7. Bxa7 Rxa7 8. Qxc2 Rxa2 9. Qxh7 Rxb2 10. Qxg8 Rxb1 11. Rxb1 Rxh2 12. Rxb7 Rxh1 13. Rxf7 Rxg1 14. Rxg7 Rxg2 15. Qxf8+ Kxf8 16. Kxf1 Rxf2+ 17. Kxf2 Kxg7

```

---
Tags: problems, records, captures
---


# Question
Title: Top players move order when playing QGD?
Why is typical move order for QGD among top grandmasters 1. d4 Nf6 2. c4 e6 3. Nf3 d5? Why does not black immediatelly go 1. ..d5? Also, why is QID via 3. ..b6 almost never played?

# Answer
There is no real objective answer, both are playable at any level. Such variations in move order are decided primarily according to roughly 3 common criteria:

* a) Comfort zone of the player: which structures they're more familiar with, and therefore, they may opt for lines that maximise the liklihood of ending up in those.
* b) The types of variations and transpositions they want to prevent from occurring (depending on the opponent), which itself depends on various elements.
* c) The kind of game they've envisaged: double edged, conservative, etc. (this is a subcategory of b) essentially), all of which influence how committal you're going to be with your starting moves.

Therefore, these matters tend to be quite opinion-based, that said, here's an attempt to shed some light on a handful of key differences between the two specific lines:

---

More particularly for the line you ask about, `1.d4 Nf6 2.c4 e6 3.Nf3 d5 ...` often called the anti-Nimzo qualifies as one of the most versatile options for black as there still remain a diverse set of variations for black to consider, to name a few (assuming `4.Nc3`):

* On the solid side: `4...Be7`\[\*\] (leading to mainline QGD with `Bf4...e3`).
* Or sharper variations such as: the Vienna `4...dxc4`
* Tarrasch `4...c5`
* Ragozin `4...Bb4`

Note that white is also keeping many options open with `3.Nf3` instead of `Nc3.`

On the other hand, with `1...d5,` well for starters, Nimzo Defence options are essentially ruled out, and assuming black is going to follow with `e6...Nf6`, white is left with early options to divert towards fundamentally different structures such as the exchange variation of the QGD: `1.d4 d5 2.c4 e6 3.Nc3 Nf6 4.cxd5 exd5 5.Bg5 ...`, compared to the move order with `1.d4 Nf6 2.c4 e6 3.Nf3 d5` where an attempt to transpose to an exchange variation with `4.cxd5 exd5` leads to poorer version of that system for white as the early `Nf3` is almost a lost tempo since black has to pressure `d5` (with early `Nc3` and `Bg5` pinning `f6`-defender) while including an early `Qc2` to prevent black from creating a good light-square bishop with `Bf5.` So the whole setup with early `Nf3-cxd5` and without `Nc3` allows only for a nonthreatening transposition to the QGD exchange variations.

Instead, by not committing to `d5` \[\**\] on the first move and playing `Nf6`, black preserves the option of playing the Nimzo among other lines (and therefore, avoid QG's altogether if so desired), while transpositions to most variations with pawn on `d5` remain open, which leads us to the natural conclusion that: not making early committal pawn moves in the centre tends to leave us with more options on the table.

---

So as you see, all these lines are possible but the decisions are made according to one's preferences (and the circumstance at hand) and neither option (`1...d5` , `1...Nf6...`) is generally better or worse.

Regarding your last question,

> Also, why is QID via 3. ..b6 almost never played?

it's not clear what you mean, the move `3...b6` is **the** defining move of the Queen's Indian Defense (QID), and it is frequently played (by e.g. Carlsen, Karjakin, Anand, Ivanchuk, ...).

\[\*\]: This mainline followed by `Bf4..e3` and `6...c5` also happens to be what Carlsen - Caruana had prepared for during the recent world championship event, see e.g. game 7.

\[\**\]: Similarly, `1...d5` also avoids certain lines that `1...Nf6` doesn't, but there's not enough time/space to get into that.
> 3 votes

# Answer
Both moves orders let Black reached a QGD guaranteed (if he wishes), but the move order with 1...Nf6 keeps White guessing. Until Black actually plays 3...d5 White has no idea if he's going to go for something like a Nimzo instead.
> 0 votes

# Answer
One possible reason to play 1...Nf6 first is to avoid the exchange variation of the QGD, which is considered a fairly good opening for white (40% white win rate and 43% draw rate in the database I'm currently looking at, compared to ~33% white win and 52% draw in the main line of the QGD for example).

```
[FEN ""]
1.d4 d5 2.c4 e6 3.Nc3 Nf6 4.cxd5

```

Of course, this is not to say that it's unplayable for the black end, but it's not considered black's best try for equality. Instead, by playing 1...Nf6 and 2...e6, black keeps his options open: if white plays 3.Nc3, black can most notably go for the Nimzo-Indian defense with 3...Bb4, which is considered to be relatively good for black and which many white players dislike playing against. When white instead plays 3.Nf3, then black can go into the QGD (if he so pleases) by playing 3...d5. At this point, any attempt at an exchange-type QGD (with 4.Nc3 followed by 5.cxd5) won't be nearly as good, as that early tempo that white has spent on Nf3 will make it substantially easier for black to consolidate his position, in particular to get his light-square bishop out while keeping his queenside pawn structure intact.

```
[FEN ""]
1.d4 Nf6 2.c4 e6 3.Nf3 d5 (3.Nc3 Bb4)

```

Of course, at the end of the day it all boils down to personal preference, especially since all of the mentioned variations are perfectly playable, even though top-level players might disdain some of them (due to the fact that top-level players operate on the smallest of edges).
> 0 votes

---
Tags: opening, queens-gambit, queens-indian
---


title: Chessbase training annotation

text:
# Question
Title: Chessbase training annotation
I am using the training annotation function of ChessBase quite extensively but have now encountered a problem. I am using ChessBase 11. When I save a game with training annotation as a pgn-file and then reopen it with ChessBase, the training questions are not triggered, but there is now text of the type

> {\[%tqu "How should White play?","","",Rg4,"Black has to play non-script moves such as ",10\]}

What could be the reason that ChessBase does not recognize the training annotation? Any ideas how I could try to solve this problem?

Thanks and kind regards, Florian

# Answer
Thanks for your answers. I have contacted ChessBase and they told me that training annotation is not supported in PGN files but just in their original database format cbh. So, there is nothing to be done about this problem.
> 3 votes

---
Tags: training, chessbase, annotation
---


# Question
Title: What is a “dual” in chess problems, such as the Babson task?
I’ve read up on Babson tasks, and they mention that all known tasks are not perfect because there are duals. I’m not sure what this means exactly. What precisely is a “dual” in chess problems?

# Answer
> 7 votes
A dual is an alternate solution, other than the intended one, *after the first move* of a problem or study. If it happens on the *first* move, the problem or study is called *cooked* instead.

> **dual**
>
> Ideally, White should have only one move at each juncture that solves a problem. If White has an alternative at any stage other than the first move, this is a *dual*. A dual is not as serious a flaw as a *cook*, and in minor lines, duals may be permissible (opinions differ on this point). Some problems make a virtue out of dual avoidance – of two apparently equivalent white moves, only one works.

(source: Wikipedia)

---
Tags: problems, terminology, composing
---


# Question
Title: How often does castling occur in grandmaster games?
May I know how to find in all grandmaster games, what the percentage of each of the following is?

* Kingside castling
* Queenside castling
* Never castled by the end of the game but still has the right to castle
* Lost the right to castle

**Note** When one side has castled more than once in a game, only the first castle counts.

# Answer
> 32 votes
If you are prepared to use standard Linux command-line tools like `wc` and `grep` then I think my free PGN processor, pgn-extract, will do much of the pre-processing necessary to count games in each category. Below is a basic bash script I put together as a proof of concept. It assumes your file of games is called `inputfile.pgn` \- adjust as necessary, or pass it in as a command-line argument:

```
#!/bin/bash
# Output stats on castling.
src=inputfile.pgn
# Pre-process the games to allow textual analysis.
pgn-extract -C -V -N --notags --nochecks --linelength 10000 -s -o stripped.pgn ${src}
# Castling by white: detect a preceding move number.
grep '\. O-O ' stripped.pgn > Wkingside.pgn
grep '\. O-O-O ' stripped.pgn > Wqueenside.pgn
# Castling by black: detect no preceding move number.
grep '[^.] O-O ' stripped.pgn > Bkingside.pgn
grep '[^.] O-O-O ' stripped.pgn > Bqueenside.pgn
# Find games in which no castling occurred.
grep -v ' O-O ' stripped.pgn | grep -v ' O-O-O ' | grep -v '^$' > nocastle.pgn

# Output the FEN of the final position to include castling rights and
# look for the presence of rights.
pgn-extract -C -V -N --notags --nomovenumbers --linelength 10000 -s nocastle.pgn --dropply -1 -F | grep ' [wb] [KkQq]' > rights.txt

# Output the results - assumes valid Result tags in the source.
echo 'Number of games: ' `grep '^\[Result ' ${src} | wc -l`
echo 'W Kingside: ' `cat Wkingside.pgn | wc -l`
echo 'W Queenside: ' `cat Wqueenside.pgn | wc -l`
echo 'B Kingside: ' `cat Bkingside.pgn | wc -l`
echo 'B Queenside: ' `cat Bqueenside.pgn | wc -l`
echo 'Neither: ' `cat nocastle.pgn | wc -l`
echo 'Rights retained: ' `cat rights.txt | wc -l`

```

I tried the script on the KingBase database (Apr 2019) and, after removing broken games and duplicates got the following stats:

```
Number of games:  2072354
W Kingside:  1633762
W Queenside:  246158
B Kingside:  1670870
B Queenside:  128124
Neither:  69776
Rights retained:  24280

```

The 'neither' figure is about 3.4% while the 'rights retained' figure is about 1.2%. If games with 20 or fewer ply are removed then the 'neither' figure reduces to about 2.9% and the 'rights retained' figure to about 0.7%.

# Answer
> 11 votes
Just googling for "castling statistics" already yields a few results; even though the analysis is done on a different set of games than 'all grandmaster games', it gives a rough indication.

**Kingside castling** is done by 80-81% of the players, and **queen side castling** by 8-9%. I estimate that **Never castled by the end of the game but still has the right to castle** is negligible (less than 0.1%, since it requires a very short game). So that leaves about 11% for the final group **Lost the right to castle**.

---
Tags: statistics, castling, grandmaster
---


title: My first tournament

text:
# Question
Title: My first tournament
I have recently got back into chess. I only really get to play online these days (May get the odd game OTB with the kids but I have only just started to teach them) I thought it might be a nice idea to try an OTB tournament maybe around September time. I live in the UK and I was wondering if anyone answers a couple of questions.

How do I find and pick the correct event?

Do you need to be a member of a federation?

What should I expect on the day of the tournament?

# Answer
> 3 votes
> I live in the UK ... Do you need to be a member of a federation?

Yes *you* do. You need to become a member of the English Chess Federation. You can do that on their website. You either need Silver membership, if you are going to play congresses only, or gold membership if you want to play FIDE rated tournaments as well.

> How to find and pick the correct event

Again the ECF maintains a calendar of events on their website. There will be events that don't appear there but the vast majority of events in England will be listed. Events will normally have different sections according to playing strength. Enter the section that best reflects your level.

It is probably also worth your while to find the nearest chess club to where you live and get in touch with them. They will have lots of good advice, particularly when it comes to local events. The ECF have a club finder page which can help you.

> How to prepare for the event.

That is really far too general a question to be answered here. I would edit your question, if I were you, otherwise it is likely to get closed for being too broad :-)

---
Tags: tournament
---


# Question
Title: Is this the only opening that allows one side to end up with three knights?
In Queen's Gambit Declined, Albin counter-gambit, Lasker trap, black ended up with three knights, which should be rare. Here white should not capture the additional knight in the next move (8. Rxg1 Bg4+ and black is winning). Are there any other openings that one side ends up with three or more knights?

```
[FEN ""]
1. d4 d5 2. c4 e5 3. dxe5 d4 4. e3 Bb4 5. Bd2 dxe3 6. Bxb4 exf2 7. Ke2 fxg1=N

```

# Answer
> 3 votes
As @JossieCalderon pointed out, any opening could end up with three knights for one side. This would always require a knight promotion of some sort. Usually, knight promotions occur to

1. Give check to the opponent immediately to move the king to another square or to save a tempo.
2. Avoid a knight fork from the opponent, or give one of your own
3. Avoid stalemate
4. Give checkmate

I think, however, that you are also asking if there is another opening where knight promotion occurs *in the opening phase of the game*. The answer is most likely "***no***".

# Answer
> 0 votes
Theoretically, any opening can allow you to end up with three knights, provided that you promote enough pawns.

---
Tags: opening, knights, queens-gambit-declined
---


# Question
Title: Is it legal to castle by tipping the rook with the king?
Nakamura castles with two hands. But I saw one of my students taking their king and "tipping" their rook towards f1.

Is this USCF/FIDE legal?

# Answer
> 4 votes
> Nakamura castles with two hands.

That's actually illegal:

> 4.1 Each move must be played with one hand only.

---

As for your student, there's no rule that you are not allowed to simultaneously move two pieces at once, and since the rules do not describe exactly *how* the king and rook reach their final squares, this is up to the player. In any case, this is *not* a violation of rule 4.4.2:

> 4.4.2 \[If a player having the move:\] deliberately touches a rook and then his king he is not allowed to castle on that side on that move and the situation shall be governed by Article 4.3.1
>
> 4.3.1 one or more of his own pieces, he must move the first piece touched that can be moved

---
Tags: rules, castling
---


title: How do I identify strong pieces?

text:
# Question
Title: How do I identify strong pieces?
Depending on the situation, some pieces that are ordinarily worth the about same value (say a knight and a bishop, or two of any piece) have different practical values because one piece is *stronger* than the other.

There's a few "strong" pieces I can think of that are a dream for an opponent to trade away.

* A centralized knight
* A fiancetto-ed bishop
* A rook on the seventh rank

I've heard that sometimes it's in a players best interest to give up a rook for a strong bishop, just to give himself some breathing room.

How do I identify "strong pieces"?

# Answer
> 4 votes
# How do I identify strong pieces?

* Read books on pawn structures (Kmoch, Soltis, Baburin etc.) Pieces are strong/weak **entirely** based on the landscape that gets carved out on the board through hostile negotiations that the purists call the *Opening.* Treacherous valleys, open plains and rocky crevices ... **all of these** get created by different pawn structures. Know the structures and you'll automatically see which pieces are going to become strong and weak well before they get to that state.
* Consider picking up some of the lighter and rudimentary books on strategy like Michael Stean's Simple Chess or Todd Barwick's Chess Strategy Workbook (which has a fantastic section description on what makes a piece strong or weak)

# How do I produce (make my pieces strong, my opponent's pieces weak) in my own games?

* Supplement your reading (see section above) with studying annotated Master Games to find these patterns and learn how the big boys **execute on** the typical plans associated with these sorts of strong-or-weak pieces. You'll slowly start to subconsciously (or consciously) emulate these ideas.
* Review your slow time-control games with a stronger player to go over opportunities where you missed opportunities to strengthen or weaken a piece. After tactical safety is established, you should always be looking to improve your pieces (or diminish the usefulness of your opponent's pieces). Sometimes just doing this is more practical (with a clock running) than some fanciful deep strategic idea that is outside most mortal club player's wheelhouses (that the more advanced books notoriously confuse people with)

# Answer
> 3 votes
Generally speaking strong pieces limit the opponents freedom. Think of the effect of your opponents strong pieces. There are important lines that you cannot challenge. There are squares you would like to occupy but cannot, either because the square is too well controlled or because the route to it is unsafe. You have pawns that are blocked. Your King is hemmed in.

When playing a game, put yourself in your opponents shoes. What would they most like to do? Can you prevent this? Permanently might be really good but if it will take them a long time that is also good. And remember that having an advantage in position often provides an opportunity for tactics. If such a chance comes up, don't miss it.

And of course you should try to prevent the opponent from establishing strong pieces. What do YOU want to do? How will your opponent try to prevent that? Can you stop him from preventing it?

Look at some well-annotated games. Read the notes and try to interpret them in the way that they relate to acquiring strong pieces. Consider if strong pieces are ever enough to compensate for being (a small amount of) material down.

---
Tags: positional-play
---


# Question
Title: Formal definition of corresponding squares
For (endgame) training purposes, I would like to write a python program (using python chess) that generates all pairs of corresponding squares in a pawn endgame. Following the definition from Dvoretsky's Endgame Manual, I define corresponding squares as squares of reciprocal zugzwang. This definition, however, does not seem to formalize corresponding squares.

Suppose we have access to a scoring function s that returns, for any position p, a score s(p) from a totally ordered domain S of scores. The maximal score means that White wins, and the minimal score means that Black wins. The simplest scoring domain is the ordered set {-1,0,1}, where -1 is a win for Black, 0 is a draw, and 1 is a win for White.

Given such a scoring function, I now define **a reciprocal zugzwang** as a position p such that s(p\_w) \< s(p\_b), where p\_w and p\_b are the positions derived from p wherein White resp. Black is to move. This definition states that White would prefer to Black to move, and vice versa.

However, this definition of reciprocal zugzwang does not yield the usual notion of corresponding squares. For example, consider the Fahrni - Alapin position. If Black is to move, White can win easily. White is to move can secure a win by means of triangulation. Nevertheless, Dvoretsky claims that the kings are placed on corresponding squares.

What would be a sensible formal definition of corresponding squares?

# Answer
Two squares A and B such that after the attacker (player going for the win) moves to square A the defender *must* move to square B to hold the position (at least for the moment).

This doesn't say that the attacker won't still win the game down the road (with objective play from both sides). But to prevent an immediate win the defender must go to B after the attacker goes to A.
> 1 votes

---
Tags: pawn-endgame, zugzwang
---


# Question
Title: What professional game has the quickest sequence, starting from move one, to quadrupled pawns?
In the blog "AJEDREZ, SIN DUDA", I came across a page that gives a game featuring quadrupled pawns.

```
[Title "Zheliandinov-T. Sereteli, 35th Championship of the USSR, Kharkov, 1967"]
[FEN "2r1kbr1/pp3pqp/5p2/3N1p2/5p2/6P1/PPn1BR1P/R2Q2K1 w - - 0 1"]

```

It occurred to me that this game might have the shortest sequence, starting from move one in a professional chess game, to quadrupled pawns. It happens here in just 18 moves.

I have three points of focus.

> 1. Is this the shortest such game that satisfies my requirements?
> 2. I cannot find the score for the mentioned game. If you can find it, please link it and put it into the replayer.
> 3. Is there a way to easily find collections of quadrupled pawn games online?

# Answer
> 4 votes
I thought it would be interesting to try a variation of @Phonon's approach and treat the search as essentially a pattern-matching task using regular expressions. So, after performing the same expansion of a FEN and isolating the central six ranks, I passed the resulting string to the `search` function of Python's `re` package, looking for occurrences of pawn characters separated by any eight intervening characters (I haven't removed the rank separators from the expanded FEN):

```
# Look for games in the given file that
# have 4 adjacent pawns in a column.
def process_file(file):
    file = open(file, encoding = "ISO-8859-1")

    # Form the regular expressions for both colours.
    white_pattern = "P........P........P........P"
    black_pattern = "p........p........p........p"

    game = chess.pgn.read_game(file)
    while game:
        board = game.board()
        for move in game.mainline_moves():
            board.push(move)
            fen = board.fen()
            # Expand the empty-square digits in the FEN to dots
            # and extract just the board position.
            pieces = "".join(["."*int(c) if c.isdigit() else c for c in fen])[:71]
            # Drop first and last ranks as they can't contain pawns.
            match_area = pieces[9:-9]
            # Give up if neither side has sufficient pawns.
            if match_area.count('P') < 4 and match_area.count('p') < 4:
                break

            if(re.search(white_pattern, match_area)):
                print(game, "\n")
                break

            if(re.search(black_pattern, match_area)):
                print(game, "\n")
                break

        game = chess.pgn.read_game(file)

```

I have kept the logic as simple as possible for clarity but an obvious improvement would be to adapt it for different numbers of pawns by generating the pattern strings using string replication.

In practice, I found the matching to be relatively slow - around 100 games per second on my machine, which would take about 8 hours to search a 3,000,000 game database. I don't know whether that speed is limited by the python-chess library or the pattern matching.

As an alternative, I tried my own pgn-extract program which can accept regular expression FEN patterns to be matched when parsing games. For quadrupled pawns, there are only 24 possible configurations for each side, so these are relatively easy to enumerate (either by hand or programmatically); for instance:

```
FENPatternI "*/???????p/???????p/???????p/???????p/*/*/*"
FENPatternI "*/*/???????p/???????p/???????p/???????p/*/*"
FENPatternI "*/*/*/???????p/???????p/???????p/???????p/*"

```

Using this approach, I was able to search a 3,200,000 game database in around 9 minutes, which is about 5,500 games per second. Interestingly, I found a slightly shorter version of something similar to the OP's original example, with the match after Black's 17th move:

[fen ""]
     [Event "CSR-chT 9091"]
        [Site "CSR"]
        [Date "1991.01.19"]
        [Round "5.2"]
        [White "Novotny, Jiri"]
        [Black "Obsivac, Josef"]
        [Result "1-0"]

```
    1. e4 c5 2. Nf3 d6 3. d4 cxd4 4. Nxd4 Nf6 5. Nc3 Nc6 6. Bg5 Bd7 7. Be2 Qa5
    8. Bxf6 gxf6 9. Nb3 Qg5 10. g3 f5 11. Nd5 Rc8 12. f4 Qg7 13. e5 dxe5 14.
    Nc5 Nd4 15. Nxd7 Nxc2+ 16. Kf2 exf4 17. N7f6+ exf6
    { 2r1kb1r/pp3pqp/5p2/3N1p2/5p2/6P1/PPn1BK1P/R2Q3R w k - 0 18 } 18. Bb5+ Kd8
        19. Ne7+ 1-0

```

# Answer
> 6 votes
Regarding your last question:

> 3. Is there a way to easily find collections of quadrupled pawn games online?

No need to look online, you can do this on your own.

I've found 3 additional examples after parsing through roughly 300000 games of a TWIC DB:

1)

```
 [fen ""]
 [Event "FSIM May"]
 [Site "Budapest HUN"]
 [Date "1996.05.13"]
 [Round "11"]
 [White "Lochte, T."]
 [Black "Gross, S."]
 [Result "0-1"]
 [WhiteElo "2220"]
 [BlackElo "2290"]
 [PlyCount "54"]
 [EventDate "1996.??.??"]
 [SourceDate "2011.01.01"]
 [StartPly "54"]

 1. e4 c5 2. d4 cxd4 3. c3 dxc3 4. Nxc3 d6 5. Bc4 Nc6 6. Nf3 e6 7. O-O Bd7 8. Bf4 Qb8 9. Nb5 Ne5 10. Nxe5 dxe5 11. Bg3 Nf6 12. Qe2 a6 13. Nd4 Bd6 14. Rad1 Bc7 15. Nf3 Bc6 16. Bh4 h6 17. Bxf6 gxf6 18. Nh4 h5 19. Qf3 Bd8 20. Qg3 Qc7 21. Qg7 Rf8 22. f4 exf4 23. Rfe1 Qe5 24. Bd5 Qg5 25. Bxc6+ bxc6 26. Nf5 Bb6+ 27. Kh1 exf5 0-1

```
2.

```
 [fen ""]
 [Event "8th World Seniors"]
 [Site "Grieskirchen GER"]
 [Date "1998.11.09"]
 [Round "2"]
 [White "Wegener, H."]
 [Black "Knebel, W."]
 [Result "0-1"]
 [ECO "B95"]
 [WhiteElo "2115"]
 [PlyCount "54"]
 [EventDate "1998.??.??"]
 [SourceDate "2011.01.01"]
 [StartPly "48"]

 1. e4 c5 2. Nf3 d6 3. d4 cxd4 4. Nxd4 Nf6 5. Nc3 a6 6. Bg5 e6 7. Bd3 Be7 8. O-O b5 9. a4 b4 10. Na2 a5 11. e5 dxe5 12. Bxf6 gxf6 13. Qf3 Ra7 14. Bb5+ Kf8 15. Nf5 exf5 16. Qe3 Qd4 17. Qh6+ Kg8 18. c3 Qg4 19. Qe3 Rc7 20. cxb4 axb4 21. Rfc1 Rxc1+ 22. Rxc1 Kg7 23. h3 Qg5 24. f4 exf4 25. Qxe7 Be6 26. h4 Qg3 27. b3 f3 0-1

```
3.

```
 [fen ""]
 [Event "Open"]
 [Site "Pula CRO"]
 [Date "2001.05.24"]
 [Round "7"]
 [White "Molnar, Be"]
 [Black "Polak, T."]
 [Result "1-0"]
 [ECO "D42"]
 [WhiteElo "2352"]
 [BlackElo "2503"]
 [PlyCount "80"]
 [EventDate "2001.05.18"]
 [SourceDate "2011.01.01"]
 [StartPly "66"]

 1. e4 c6 2. d4 d5 3. exd5 cxd5 4. c4 Nf6 5. Nc3 e6 6. Nf3 Be7 7. cxd5 Nxd5 8. Bd3 Nc6 9. O-O O-O 10. Re1 Bf6 11. Be4 Nce7 12. Qd3 h6 13. Ne5 Nxc3 14. Qxc3 Nf5 15. Be3 a5 16. Rad1 a4 17. Ng4 Bg5 18. Bxf5 exf5 19. Bxg5 hxg5 20. Ne5 Qa5 21. Qc4 Be6 22. d5 Rac8 23. b4 axb3 24. Qxb3 Rc5 25. Ng6 Rc3 26. Qxb7 Rc7 27. Qb1 fxg6 28. Rxe6 Kh7 29. d6 Rd7 30. Qb3 Rfd8 31. g4 Qc5 32. Qd5 Qxd5 33. Rxd5 fxg4 34. a4 Ra8 35. Re7 Rdd8 36. a5 Ra6 37. d7 Ra7 38. Kg2 Raa8 39. Rxg5 Ra7 40. Rd5 Raa8 1-0

```

---

**Briefly, how I've done it in Python and using python-chess to read the PGN DB:**

I scan through each game of the DB mapping each position to its FEN, then I expand the FEN by replacing numbers with a corresponding amount of dashes '-'. In the FEN notation numbers in between the rank '/'-separated sections denote how many empty squares there are before a piece reached on a given row) so e.g., this FEN

```
'3r4/3PR1pk/r5p1/P2R2p1/6p1/8/5P1P/6K1'

```

becomes:

```
'---r----/---PR-pk/r-----p-/P--R--p-/------p-/--------/-----P-P/------K-'

```

which you can easily do as follows:

(after removing everything after the first space `fen=fen[0:fen.index(' ')]`)

```
def isinteger(s):
    try:
        int(s)
        return True
    except ValueError:
        return False

for el in fen:
        if isinteger(el):
            fen = fen.replace(el,int(el)*'-')

```

Then we know we want to find consecutive rows having pawns (of same color) on the same files, so if you split the FEN string according to the '/' separators into a list (`splitfen = fen.split('/')`), you have to match the pattern that letter 'p' (denoting black pawns in FEN, similarly, 'P' for white) occurs in 4 consecutive elements of the list and at the same position of the strings of size 8 (to ensure they're on same file) which you can go about in many different way:

```
#(the function that finds all consecutively matching patterns for t)
def checkpattern(sp,t):
    start = [sp[0]]
    for i in sp[1:]:
        if any(all(t == c for c in b) for b in zip(*(start+[i]))):
            start.append(i)
        else:
            if len(start) > 1:
                yield start
            start = [i]
    return

splitfen = fen.split('/')

forblack = list(checkpattern(splitfen,'p'))
forwhite = list(checkpattern(splitfen,'P'))
total = forblack+forwhite
  for el in total:
    if len(el)==4: #(since we want quadrupled pawns)
      res = True
      break

```

All such kinds of search queries across chess DB's can be easily performed with a bit of scripting around the FEN to spot the wanted patterns (be they pawn structures, number of pieces etc).

# Answer
> 3 votes
I found the game in the chess365.com database. Here's the link.

Here is the search that I used to find it.

Here's the game in the replayer.

```
[FEN ""]
1.  e4  c5 2.   Nf3 Nc6 3.  d4  cxd4 4. Nxd4    Nf6 5.  Nc3 d6 6.   Bg5 Bd7 7.  Be2 Qa5 8.  Bxf6    gxf6 9. Nb3 Qg5 10. Nd5 Rc8 11. O-O Rg8 12. g3  f5 13.  f4  Qg7 14. e5  dxe5 15.    Nc5 Nd4 16. Nxd7    Nxc2 17.    Rf2 exf4 18.    N7f6+   exf6 19.    Bb5+    Kd8 20. Rxc2    fxg3 21.    Qd4 1-0

```

I also found this collection of games with isolated triple pawns. Might be helpful.

Some google searching found a famous quadrupled pawn game played by the great Alekhine.

```
[fen ""]
1. d4 d5 2. Nf3 e6 3. e3 c6 4. Bd3 f5 5. Ne5 Qf6 6. Nd2 Nd7 7. f4 Nxe5 8. fxe5 Qf7 9. O-O Qc7 10. c4 Nh6 11. b3 Bd7 12. a4 Be7 13. cxd5 cxd5 14. Ba3 Bxa3 15. Rxa3 O-O 16. Ra2 Rac8 17. Qe2 Qb6 18. Rc2 Rxc2 19. Bxc2 Rc8 20. Bd3 Qb4 21. h3 Nf7 22. Rb1 Rc3 23. Kh2 a6 24. Qf1 Qa3 25. Rd1 Qb2 26. Qe2 Nd8 27. Rb1 Qa3 28. Rf1 Qb4 29. Bb1 b5 30. g4 bxa4 31. gxf5 Bb5 32. Nc4 Rxb3 33. fxe6 dxc4 34. Qf3 Rxb1 35. Rxb1 Qxb1 36. e7 Ne6 37. d5 Qg6 38. dxe6 Qe8 39. Qd5 h6 40. Qc5 c3 41. Qxc3 Qxe7 42. Qc8+ Qe8 43. Qc7 Qxe6 0-1

```

Also, check out @Phonon 's answer; it holds additional games.

---
Tags: pawns, pawn-structure, records, master-games, famous-games
---


# Question
Title: Why is 6. a3 a mistake compared to Qa4+?
I played a game on lichess recently. Afterwards, I used the analysis feature, including the "learn from your mistakes" feature, and it said that 6. a3 by white was a mistake, with 6. Qa4+ as best. I'd like to know why, as I don't understand why 6. Qa4+ is superior.

\[After Qa4+ , it seems to me black can play 6. Nc6, and if the white queen captures the black knight, 7. Qxc6, it seems to lead to a draw as the white queen cannot escape capture threats starting with 7. Bd7 by black.\]

```
   [FEN ""]

   1. d4 d5 2. e3 { D00 Queen's Pawn Game } a6 3. c4 b6?! { (0.12 ? 1.07) Inaccuracy. Best move was e6. } (3... e6 4. Nf3 c5 5. cxd5 exd5 6. Nc3 Nf6 7. Bd3 c4 8. Bc2) 4. Nc3?! { (1.07 ? 0.50) Inaccuracy. Best move was cxd5. } (4. cxd5 Nf6 5. Nf3 Bb7 6. Be2 Qxd5 7. Nc3 Qd6 8. O-O Nbd7 9. Nd2 e5 10. Bf3 c6) 4... e6 5. Nf3 Bb4? { (0.17 ? 1.63) Mistake. Best move was Bb7. } (5... Bb7 6. b3 Nf6 7. Bb2 Bd6 8. Bd3 O-O 9. O-O Nbd7 10. h3 c5 11. cxd5 exd5 12. Ne2) 6. a3? { (1.63 ? 0.59) Mistake. Best move was Qa4+. } (6. Qa4+ Nc6) 6... Bxc3+ 7. bxc3 f6?! { (0.65 ? 1.60) Inaccuracy. Best move was Nf6. } (7... Nf6 8. cxd5 exd5 9. Be2 Nbd7 10. O-O O-O 11. a4 c5 12. c4 Bb7 13. Bb2 Rc8 14. Nd2) 8. Qc2 g6 9. cxd5 exd5 10. c4 Ne7?! { (1.74 ? 2.43) Inaccuracy. Best move was Bf5. } (10... Bf5 11. Bd3) 11. cxd5 Qxd5 12. e4?! { (2.47 ? 1.93) Inaccuracy. Best move was Bc4. } (12. Bc4 Qd6 13. O-O Be6 14. d5 Bf7 15. Rd1 b5 16. Ba2 Nd7 17. e4 O-O 18. Be3 g5) 12... Qd6 13. Be2 Bg4? { (2.31 ? 3.33) Mistake. Best move was Bb7. } (13... Bb7) 14. Bb2?! { (3.33 ? 2.57) Inaccuracy. Best move was O-O. } (14. O-O Nd7 15. Rd1 h5 16. h3 Bxf3 17. Bxf3 Kf7 18. a4 Qc6 19. Qd3 Qe6 20. Bf4 c6) 14... Nbc6?! { (2.57 ? 3.07) Inaccuracy. Best move was Nd7. } (14... Nd7 15. O-O O-O 16. Rfd1 c6 17. a4 Rfe8 18. Ba3 Qb8 19. Qb3+ Kh8 20. Bc4 Kg7 21. Bf7) 15. d5? { (3.07 ? 1.98) Mistake. Best move was O-O. } (15. O-O) 15... Bxf3 16. Bxf3 Ne5 17. Be2 b5 18. O-O O-O 19. Bd4 Rac8?! { (2.29 ? 3.12) Inaccuracy. Best move was f5. } (19... f5 20. Bc5 Qd7 21. Rfd1 Nf7 22. exf5 gxf5 23. d6 cxd6 24. Qb3 d5 25. Qg3+ Ng6 26. Bxf8) 20. f4? { (3.12 ? 1.35) Mistake. Best move was Bc5. } (20. Bc5 Qd7) 20... Nc4? { (1.35 ? 3.56) Mistake. Best move was Nd7. } (20... Nd7) 21. Bxc4 bxc4 22. Qxc4 c5 23. Be3 Kg7? { (3.59 ? 4.87) Mistake. Best move was f5. } (23... f5 24. Rac1 fxe4 25. Bxc5 Qxd5 26. Qxd5+ Nxd5 27. Bxf8 Rxf8 28. g3 Nf6 29. Rc6 a5 30. Ra6) 24. Rac1 f5? { (4.67 ? 6.59) Mistake. Best move was Qd7. } (24... Qd7 25. Bxc5 a5 26. Qc3 a4 27. Qd4 Rfd8 28. Rc4 Qe8 29. Rfc1 Qf7 30. Rxa4 Nxd5 31. exd5) 25. Bxc5 Rxc5?! { (5.89 ? 6.59) Inaccuracy. Best move was Qd7. } (25... Qd7 26. Qc3+) 26. Qxc5 Qxc5+ 27. Rxc5 fxe4 28. d6 Nf5 29. d7 Rd8 30. Rd1 e3 31. Kf1 Ne7?! { (6.49 ? 7.39) Inaccuracy. Best move was Kf8. } (31... Kf8 32. Ke2 Nh6 33. Ra5 Ke7 34. Rxa6 Ng4 35. a4 Nf2 36. Rd4 Ng4 37. h3 Nf6 38. Kxe3) 32. Ke2 Nf5? { (7.22 ? Mate in 10) Checkmate is now unavoidable. Best move was Kf7. } (32... Kf7 33. g4 a5 34. a4 h5 35. gxh5 gxh5 36. Rxa5 Ng6 37. Kxe3 h4 38. Rad5 Ke7 39. a5) 33. Rc8 Rxd7?! { (24.96 ? Mate in 8) Checkmate is now unavoidable. Best move was Kh6. } (33... Kh6) 34. Rxd7+ Kf6 35. Rc6+ Nd6 36. Rcxd6+?! { (Mate in 2 ? Mate in 2) Not the best checkmate sequence. Best move was g4. } (36. g4 a5 37. Rcxd6#) 36... Kf5 37. Kxe3?! { (Mate in 2 ? Mate in 4) Not the best checkmate sequence. Best move was Kf3. } (37. Kf3 g5 38. Rf7#) 37... Kg4 38. Rxh7 g5 39. fxg5?! { (Mate in 3 ? Mate in 4) Not the best checkmate sequence. Best move was Ke4. } (39. Ke4 a5 40. Rg6 a4 41. Rxg5#) 39... Kxg5 40. Rc7 Kf5 41. Rc5+ Kg4 42. Rd4# { White wins by checkmate. } 1-0 *

```

# Answer
**In short**: `Qa4` forces black to lose grip over central light squares as black is tactically being restricted to recapturing with a queen on `d5` instead of a pawn, leading to:

As opposed to any of the actually desirable and common setups for black, which might look like: (with `Nf6` instead of `Bb4`, and quick `Bb7` and castling being prioritized)

It helps to try and understand the purpose of every move at a basic level, let's start with your 3rd move `c4:` Clearly, one of the most common and signature moves of all queen's pawn games, but what purpose does it serve?

Openings are a lot about taking control over the centre and not conceding it easily to your opponent, so when white plays `1.d4`, they're claiming control over dark squares, namely `e5` and `c5,` similarly, black replying with `1...d5` they're reciprocating by controlling `c4` and `e4` (so light square control). And that brings us to the famous `c4` move, which attempts to undermine black's control over light square, so whenever white manages to force black's hands into either taking on `c4` or recapturing on `d5` with a non-pawn piece, you could say white has achieved a small success in central control, which among other options may allow white to play `e3-e4-e5` and take away more squares from black's minor pieces. These ideas should make it a bit more intuitive as to why, *black recapturing with a non-pawn* ought to be a strategic gain for white. Let's summarise with a diagram, in blue the desired central setup with `d4-e4`, and the green `c4` the enabler, and in turn black's intends to keep maintain grip over `d5` with `e6/c6.`

Now let's have a closer look at your game: `5...Bb4` by black is a terribly odd and poor move: black is playing rather inconsistently, first opting for an early queen-side development with `b6` to fianchetto their `c8` bishop, but then develop their dark squared bishop, temporarily ignoring the created light square weaknesses, in particular `c6`. Moreover, bishop developments before knights are possible but rather rare, in general knights are more easily developed (as their restricted movement makes their optimal development easier to resolve given a structure), and they in turn create useful space for the bishops. And your game makes for a perfect example of such careless development as it can be tactically exploited with an immediate `Qa4+` which:

* Forces `Nc6`, which is not only a non-ideal knight placement in this position (the structure tends to favour developments of the type `Nd7-Bb7-Nf6-Be7` with an early `c5` to challenge white's centre, impossible with a knight on `c6`) but it also allows white to force a queen recapture on `d5` after `cxd5.`
* After `7.cxd5`, black can either take on `c3` first with check, or take on `d5` with `Qxd5` immediately as the knight on `c3` is pinned. Obviously, `exd5` is not a choice as it outright blunders `c6` since the queen will no longer be caged as it can take on `d5` afterwards.
* Not only white will have fully claimed the centre, but they will also be much ahead in development and black has a real struggle ahead to even meaningfully finish development (no prospect for active knights, open files and rook activity ...) while parrying white's upcoming threats, to showcase with one possible scenario, after `7...Qxd5 8.Bd3 Ne7 9.O-O Bxc3 10.bxc3 O-O 11.e4 Qd8` we reach the following position:

Note that black conceding the `d5` pawn with either `dxc4` or a non-pawn recapture would be acceptable provided they could maintain sufficient light square control with their minor pieces afterwards, e.g. a knight on `f6` and a fiachetto'ed `b7` bishop. The latter may further justify the opening of the long diagonal for creating active play against white's king.

Last but no least, at a rough basic level similar to our earlier discussions, there are openings where black even encourages white towards an early advancement of central pawns, which black aims to exploit by either fixing the structure and therefore inducing a weakness (like the King's Indian Defence) or by actively trying to undermine the central structure in order to create a weakened target (such as the Grünfeld Defence), all backed by an early kingside development.
> 7 votes

---
Tags: analysis
---


title: Is black in check?

text:
# Question
Title: Is black in check?
I know this sounds like a really basic question, but I couldn't find it anywhere on the site... On the following board, is the black king actually in check (assuming it's his move)? My thoughts are just that white technically should not be allowed to move his bishop away, as it would place his king in check.

My *guess* would be that black *is* in check because white could take his king before black could take his, but I'm looking for confirmation / refutation...

I guess what really made me ask the question was when I was placed in a situation in a chess game where I was in a similar situation, but I was able to place the white king in checkmate; something like this:

...where rook to a7 results in a checkmate for white.

Again, I have a feeling that the fact that white is in direct line to take black takes precedence over the rule that you are not allowed to put yourself in check by your moves, but again, I'm looking for confirmation / denial. Thanks!

# Answer
> 2 votes
Yes, black is in check. Pinned pieces are able to give check.

In your second position, `Ra7#` is an illegal move. Black is in check, and thus must get out of check immediately.

---
Tags: checkmate, check
---


# Question
Title: Are today's top correspondence chess players stronger than those from 5 years ago?
On the one hand today's chess engines will stomp those from five years ago no problem, not to mention hardware improves; on the other hand, correspondence chess players emphasize that one can't just rely on the engine to play:

> DN: Every how often do you have to change your machine?
>
> WM: I've never changed my 'machine'. If we're talking about my computer for chess analysis, I'm using the same computer I've had since 2008. Modern correspondence chess isn't all about CPU power (although that obviously helps), but more about how you prepare each move and how you work with the engine in tandem with your own ideas. You can get lazy and buy a powerful computer, and probably get to a fairly decent rating on ICCF just parroting the engine, but that's not going to take you to the top ...

Are today's top correspondence chess players able to reliably beat those from five years ago?

Related: Are contemporary chess players now stronger than players in the 90's or 80's?

# Answer
Yes, mainly due to more advanced theory that wasn't known five (or more) years ago.

Also, while top Correspondence players do indeed combine engines with their own ideas, having an Engine that is a few hundred rating points higher is a definite factor. I find it hard to believe the person you quoted uses the same engine he has for 10 years. If he means the same computer though (so running the most recent Stockfish/Komodo/Houdini on an old computer), that sounds more understandable. In this case he's only sacrificing the amount of speed that a PC 10 years older gives up compared to PCs now.
> 4 votes

---
Tags: history, correspondence-chess
---


# Question
Title: How many different knight's tours are there?
How many solutions does the Knight’s Tour puzzle have when the knight first moves from square a1, through all squares (on each square once), and return back to a1? Please give some solutions. Also, does the Knight’s Tour have any solutions for starting from any random square?

# Answer
> 6 votes
Wikipedia quotes several sources for a count of 26,534,728,821,064 for the number of closed directed tours of the 8x8 board. As **Brian Towers** notes in his answer, that is equivalent to the count of Knight's tours starting from some given square (such as a1) and ending on the same square. The same Wikipedia page exhibits several such tours.

# Answer
> 5 votes
> Please share some solutions.

If you use the search function (top left corner of the screen) you will find this answer with a beautiful picture of the moves.

> And also has this puzzle solutions from any random square?

If you stop and think about it for a moment you will realise that if the knight starts on a1, moves through all the other squares exactly once before returning to a1 then that sequence of moves constitutes an answer for every square on the board. Hence every solution where the knight returns to the same square is a solution for every square of the board. This was also pointed out by Aric in his answer above.

---
Tags: puzzles, knights, calculation, mathematics
---


# Question
Title: Looking for a single, good opening that revolves around a “crab” pawn structure
I have often heard (or this one video just got it stuck in my head) Youtube videos (the timestamp is 2:37, nothing else relevant) refer to this kind of pawn structure as a “crab” pawn structure (below, white pawns.) The name makes sense because it is like a crab pincer enclosing the board, as agadmator said.

This is just an example; it is not to be analyzed.

```
[FEN ""]
[startply "8"]

1. e3 f5 2. f4 Nf6 3. c4 c5 4. d3 Nc6

```

Is there a good opening that revolves around such a “crab” pawn structure? I seek merely one, not all possible ones. As long as the structure of the pawns, as shown in the example, is the same, the “crab” can be anywhere on the board.

I would like to utilize such an unorthodox playing method to surprise opponents. I would like to know the advantages/disadvantages of the opening, such as how to counter/play it. There is no need to cover all possible variations.

# Answer
> 1 votes
One disadvantage of the position in your diagram is that the pawns on d3 and e3 are "backward". That is, there are no pawns behind them and they cannot be safely advanced. Backward pawns are often a target for the opponent to aim at.

One advantage is that all four center squares are covered by your pawns.

This pawn structure, if shifted one file towards the queenside, can arise from the Giuoco Pianissimo, among other openings. For example, the following is perfectly reasonable and has been played by multiple grandmasters:

```
[FEN ""]
1. e4 e5 2. Nf3 Nc6 3. Bc4 Bc5 4. c3 Nf6 5. d3 O-O 6. b4 *

```

Here's a game from 1857 where Paul Morphy wins against this structure, arising from a Roy Lopez opening:

```
[Site "New York (USA)"]
[Date "1857.??.??"]
[White "Meek A"]
[Black "Morphy Paul"]
[Result "0-1"]
[ECO "C65"]
[FEN ""]

1.e4 e5 2.Nf3 Nc6 3.Bb5 Nf6 4.d3 Bc5 5.c3 d6 6.b4 Bb6 7.a4 a6 8.Bc4 Be6 9.Bxe6 fxe6 10.O-O O-O 11.Ng5 Qe7 12.Kh1 h6 13.Nh3 d5 14.Ba3 Nd8 15.b5 Bc5 16.Bb2 dxe4 17.d4 exd4 18.cxd4 Bd6 19.Nc3 axb5 20.axb5 Nf7 21.Qe2 Qd7 22.Nxe4 Nxe4 23.Qxe4 Qxb5 24.Rab1 Qd5 25.Qg4 Ra4 26.Nf4 Qe4 27.Bc1 Bxf4 28.Bxf4 Rxd4 29.Qh3 Qxf4  0-1

```

# Answer
> 3 votes
To answer your question, there are no good openings that revolve around this "crab" pawn structure. This is because this structure takes a lot of pawn moves, decreases the mobility of your bishops, and creates weakness on the kingside. It would even be difficult to come up with a respectable variation of any opening that has this pawn structure (perhaps the variation in the link provided is playable, but I don't think it gives an objective advantage). Of course the pawn structure in the link is different than the one you displayed. Either way, I recommend avoiding these "crab" structures at all costs. If you want to surprise you're opponent with unorthodox openings in an aggressive manner, try some gambits out. For example, King's Gambit, Smith Morra Gambit, Evans Gambit, etc.

---
Tags: opening, pawn-structure
---


# Question
Title: At what point does this mental trick stop working?
Sometimes, I'll be in a position where my opponent is threathening to do something and I cannot stop it. So, in response, I play a move that looks pretty dangerous and clever, but which I in fact have not managed to calculate all the way through and I have no idea whether it will work or not.

And I often see that in such situations, the opponent becomes overly paranoid and thinks I've just played some sort of mastermind move, and then they start retreating or playing too defensively or whatever, and I manage to weazel my way out of the situation.

When I then go back and analyze my play with the engine, it will often tell me that my clever move was a complete mistake and my opponent wins by just doing the obvious thing they were about to do.

At what point do these mental tricks, where you make dangerous-looking movies to make your opponent overly paranoid, stop working? I'm thinking there must be some point where players simply become too good to be fooled by that sort of trickery, and just calmly make decisions based on pure calculation.

I currently play in the 1600-1700 range on lichess.

# Answer
This trick is prevalent in all levels. Of course, depending on the position, your ability to muddy the waters varies. Against much higher rated opponents, it is typical that they will gain an advantage without giving you much counterplay. Nevertheless, in all levels of the game, the losing side will try to muster some counterplay to get back into the game. You make a comment about moves that look dangerous but are not. The higher rated your opponents are, the more likely they will realize that your plan is not dangerous. Often, it will be better for the losing side to defend and wait for the right time to strike than to go all out on a dubious plan. Furthermore, many positions, even in the top levels, can be wildy complicated to calculate, and the objective evaluation is not always a good predictor of outcome even at the top levels. Thus, not even grandmasters will always be able to evaluate the position accurately from "pure" calculation. So to answer your question more precisely and perhaps unsatisfactorily, if you make a dangerous looking move, if it is "obvious" to your opponent that it's unsound, you'll be punished. Where "obvious" depends on the strength of your opponent and the subtleness of your clever move.
> 8 votes

# Answer
If you're losing, then attempting to complicate matters is a good idea. It gives your opponent a chance to go wrong and you a chance to recover. I've saved many games by aggressive moves that upon scrutiny could be found wanting. If your opponent stays calm and analyzes them thoroughly, then chances are they probably won't work. But nothing has been lost by trying.
> 4 votes

# Answer
Depends on how much experience people have dealing with bluffing. The trick you mentioned can be effective at all levels, but against a 2000+ player (with lots of experience) it's likely to not have too much of an effective.

Still, the tactic has been used by GMs against other GMs successfully in the past. Karpov was once down a clear exchange against another top player in the world. He played so confidently that he messed his opponent up and either drew or won.
> 1 votes

# Answer
This is not a mental trick, this is how chess should be played!

If you cannot stop your opponent's attack, you'd better find yourself some counterplay. Of course, you won't always be able to calculate the consequences of your moves, but who cares? If you can pick between a weird success possibility and a certain faillure, the choice is not hard!

As your level increases, the "mental trick" won't move away, you will just learn how to create more subtle, precise ones, and also how to predict your opponents plan and react before!
> 1 votes

---
Tags: strategy, rating, psychology
---


title: Color-coding moves and games

text:
# Question
Title: Color-coding moves and games
If you are familiar with watching chess broadcasts on ChessBomb, you'll know they have an engine running on the server which evaluates moves, and colors each move according to whether (according to SF) it was the correct move, an imprecise move, a mistake, a blunder etc. with colors ranging from bright blue (good) to bright red (bad). When switching to a game, one can then instantly see how well the game was played, and where a blunder/mistake may have occurred.

Does anyone know if a similar feature is available in other chess software or websites where one can upload their own games? And get such color codings for their own games?

I'm only looking for something equivalent or very similar to this; I know some software uses graphs to display the +/- score as a function of the move number, and some software can auto-analyze all moves and annotate it with ? and ?! and such. I'm not looking for that.

Edit: below is an example of what I mean, when viewing a game in the mobile browser. It instantly shows all the moves and highlights which moves were good/bad.

# Answer
Here's how color-coded analysis looks on the lichess desktop site.

As you can see, depending on the severity of the error (according to Stockfish), different colored bars pop up on the game analysis - blue for an inaccuracy, orange for a mistake, and red for a blunder. A black bar will show if a player loses a forced checkmate sequence or blunders into a forced checkmate sequence. I don't have the app, currently, but I believe that the same thing shows up there, since I used to play exclusively on the app.

You get this color-coded analysis by clicking "request a computer analysis" - it's on the bottom of the screen on PC.

If anyone has the app downloaded at the moment, feel free to screenshot this feature and add it to this answer.
> 2 votes

---
Tags: engines, software, evaluation
---


# Question
Title: Why is the algebraic notation not just two numbers?
Instead of 'a1', why not '11'? First file, first rank.

Instead of 'g6', why not '76'? Seventh file, sixth rank.

And so on. Why not just use two numbers to represent the square, as opposed to 1 letter and 1 number?

I think the notation with the letter is more confusing for beginners and children. For example, with the 'g6'-square, it's not immediately obvious to a complete beginner where the 'g'-file is. They usually have to look down on the letter on the chess board, or, if the board doesn't have letters, they will usually count in their head, from left to right: 'a ... b.. c.. d.. e ... f... g, aha there it is'. On the other hand, if the 'g'-file was simply the '7'-file, it's immediately obvious where it is, since it's much easier to simply find the 7th file by eye-sight.

# Answer
Imagine White has two knights on b5 and e2 respectively (ie, 25 and 52) I think it would be confusing to write N243 rather than Nbd4 (we could still write N5d4, making a "mistake" but still not changing our move)

Also, there is no advantage to write everything in numbers, I'd say it loses legibility, as now our eyes can easily tell pieces (capital letters), files (lowercase letters) and ranks (numbers)
> 6 votes

# Answer
I believe that it is more of a historic thing where chess players went from descriptive to algebraic notation, really because strong players started adopting algebraic notation. Admittedly, using 2 numbers would probably be just as easy to use once you get use to it. Infact, ICCF(international correspondence chess federation) uses such coordinate systems in order not to confuse people from different countries who would use different alphabets for algebraic notation.
> 5 votes

# Answer
One reason would be to avoid confusion with earlier methods - such as numbering each square from 1 to 64, starting on black's side of the board.

"28" could either be file 2, rank 8 (b8), or the 28th square from the upper left (d5).
> 3 votes

---
Tags: notation
---


# Question
Title: What is the best strategy for white in this position?
```
1n3r2/q4pbk/3p2pp/r1pPp3/1pB1P3/1P2BP2/2PQ2PP/3R1RK1 w - - 0 1

```

I was white in the diagram position in an OTB game I played recently. However, I couldn't find a satisfactory plan. Playing f4 is always tricky because it vacates the e5 square for the black knight and opens up the diagonal for the black bishop. I have the feeling I evaluated this position wrong and it is in fact just equal and not better for white. Any thoughts?

# Answer
I think the f4-plan is doomed to fail. It would be beautiful if we could achieve it in good conditions, however, as you pointed out, f4 is met with ...exf4 followed by probably ...Qe7 and Nd7-e5. We get rid of the pressure on the 'a' file though, so it's better than doing nothing.

If we went for g3, preparing for gxf4 after f4, our effort will be met by ...f5! shattering our dreams.

It would be interesting to try to put our light-squared bishop on a4, but I don't see it working either after 1.Qd3 Nd7 2.Bb5 and now even Nb6 does fine

For those reasons, I think the best answer here is to immediately play c3!? It's true that Black has ...Ra2, but after Qe1 I don't really think it does much. If Black captured on c3, our queen would be now in a great square to fight for the a file. If Black does NOT capture, then we can begin to put some pressure on b4
> 9 votes

# Answer
I see a couple ideas:

First your f4 idea seems reasonable. Consider 1.g3 with the idea of f4 when the threat of f5 is good. If Black plays exf4 then gxf4 controls e5. You can even re-deploy the Bishop from c4 to h3 to control the knight.

The second idea, which seems like a clear edge for White to me, is to trade the queen-side pawns by playing c3 and eventually b4. This will expose the d6 pawn as weak while completely destroying Blacks space advantage on that side of the board.

> I would play 1.c3

Don't worry about 1...Ra2 that is just a temporary nuisance; simply Qe1 and Black has to deal with the threat of cxb4. On bxc3 2.Qxc3 followed by Ra1 takes over the a-file. Black is suffering here.
> 2 votes

# Answer
I would not go for f4, since it opens up the Black's Bishop on g7. It becomes really strong after exf4. My instinct would be to go for the other pawn break: c3! Although this gives Black the immediate Ra2, imagine the response Qe1. The Queen looks very backwards, I know. However, cxb4 is a threat. If Black plays f5, it can be ignored; taking opens up his bishop! Therefore, also in this position cxb4 is possible. But why Qe1? To keep focus on c3 and prepare Ra1, getting your rook to an open file. Be careful though, don't play Ra1 without good preparation. imagine: 1. Ra1 Rxa1 2. Qxa1 Qxa1 3. Rxa1 bxc3 4. Rc1 Nd7. It can become awkward with Ra8, again taking the open file. So: Ra1 may be awkward if the tension between c3 and b4 is still there. I would prefer playing cxb4 first. If your opponent were to take your pawn on c3 before you've played Ra1, just Qxc3 and Ra1 would be fine.
> 0 votes

# Answer
My thought looking at the position is you want to attack Black's king, so if you don't want to play f5 at once, then a possible plan is to play Rf2, g5, Rg2, Rg3, Rh3, increasing the pressure on h6.

This is quite slow, but black doesn't seem to have an obvious way to generate counterplay.

Black might defend h6 by putting his Knight on g8, perhaps play f5 at that point.

\[ I am not much good, so take this with a big pince of salt! \]
> 0 votes

# Answer
Whites position is much better/winning due to double bishop advantage, space advantage and black's poor dark square bishop.

f4 looks like a good plan, however it needs preparation with g3. It threatens f5 with f6 which will completely crush black's position.

c3 looks pretty good as well, breaking up black's queen side.

Of course all of this is my speculation and you should just use an engine to see white's best plan.
> -1 votes

# Answer
Matthew- Before claiming that something is strong you have to point out what it enables. This is the counterpart to the truism that nothing is weak unless it can be attacked. It is also true that nothing is strong unless it can be used to attack.
> -1 votes

---
Tags: strategy
---


# Question
Title: Why should I try to put knights on weak squares when they can be taken easily?
Here you can see two weak squares-b6 & d6. That's what my chess book says, and in order to use these two weak squares, one must consider the moves Nf3-d2-c4.

Actually, the story is more complicated (black has the strong reply ...Nc5, but for me it doesn't matter for the moment).

When I searched good ideas for white, I saw the two weak squares, but my thoughts were : "Okay, there are two weak squares, but 1/ Nd7 can take at b6, it is well put at d7 to do that 2/ for e6, Nf6 can move to e8, and moreover Bg7 can move to f8. So the two squares are not useful for me".

As a chess player, could you give me some reasons for not rejecting the positioning of knights or bishops on weak squares? Should I always try to put them on such squares, hoping the exchanges will end with a better position for me?

# Answer
It is true, that sometimes occupying weak squares with your pieces will just lead to exchanges and no advantage whatsoever. But there is a well known dictum in chess, that "the threat is stronger than the execution". This means that just threatening to occupy a weak square can severely restrict your opponent's possibilities. Just imagine you brought a knight to c4 and your opponent was set on the idea to either play Nd7xb6 or Nf6-e8 if you dropped your piece into b6 or d6. This would leave him unable to move either knight until you executed your threat. Which in turn would hamper his development, because his bishop cannot move, which in turn means his rooks cannot be connected. And of course you wouldn't oblige him and execute your threat, you would just keep it hanging over his head.

On the other hand, in this specific position, taking the knight on b6 wouldn't solve blacks problems. After you retake with the bishop you actually control the square d8. This is very relevant, because it means that he cannot oppose you with his rooks on the d-line. So, bringing a knight to b6, retaking with the bishop and then taking control of the d-line by doubling your rooks, seems like a valid plan to use the weakness of b6.

Of course these are purely strategic musings, it is always the question whether a plan can be executed tactically.
> 16 votes

# Answer
A good way to better understand this position is to try and play it with black. What you'll quickly notice that the Nd7 is awkwardly placed as it's blocking the Bc8 which in turn virtually stalemates the Ra8. Black has a handful of semi-useful moves they can try before they start looking for a new square for the Nd7, like moving the Nf6 to push f5 and perhaps move the Rf8 but ultimately the Nd7 WILL have to move. This means that the b6 square will inevitably become available for a white piece; whether that'll be relevant depends entirely on other decisions made by black, however.

As for the d6 square, you definitely shouldn't be concerned about a knight defending it from e8. If black doesn't immediately lose tactically, they'll certainly have to sooner or later face the consequences of playing two rooks down.

Weak squares are undoubtedly a feature of the position you have to keep in mind but to me it's actually more important to determine what the ideas or plans for black can be and search for ways to prevent them or at least render them ineffective. Considering black's King's-Indian-like setup, if it were black to move, then they'd most likely go for the Nc5-Ne6 maneuver, assuming you aren't going to give up your DSB for a knight if you want to win the game. Nc5 can nevertheless be prevented by moving your queen to c4, which also gives your LSB a little more scope and frees up the d file for a rook. Qc4, moreover, will threaten Bc5 should the Nd7 go elsewhere. Lastly, it pins the f pawn to the king, which rules out f7-f5 for the time being. The white queen can always move away from c4 to allow for the Nd2-Nc4 maneuver later on. An engine might always come up with a better move, though, I haven't checked.

Remember that tactics flow from a superior position and a position where your opponent has all their pieces on the back rank certainly is superior for you. When your opponent has to make passive retreats with no potential to create counterplay, you have to treat it as one of a number of small strategic victories that you can accumulate until you gain a decisive advantage.
> 1 votes

# Answer
This is a profound question. I merely offer a few points to keep in mind.

You can't avoid all weaknesses. In your position d6 is weak because Black has played c6. But if he had not played c6 then d5 might be a weakness. You need to judge which would be more serious.

Simply arriving at a weak square is not a great achievement unless there is something for the piece to do when it gets there. In your position b6 is perhaps weak, but weaknesses far from the center of the board are often not very important because other potential attackers cannot coordinate with it.

It is not always important to take advantage of weaknesses immediately. There is little that White can do directly in this position but he can make sensible developing moves like Rad1 and Rfe1 and Qc4. Black does not have a similar set of "useful little moves" if he needs to keep his weaknesses defended.

A weakness is not serious if it takes a long time to reach it. Even if you give White a lot of free moves, how does that Knight arrive on b6? The problem is that both the Knight and the Queen want to use c4.

You do not include c5 in your list of weak squares, but it can only be defended by b6. Given Blacks frequently occurring Pawn structure this is often important.

If White had known Blacks setup in advance, he could have placed his pieces more effectively. For example move Nf3 to b3, Pf2 to f3, Qd3-f2 and the Black position looks very porous. You have treated this position where the weaknesses (if such they are) are already present. There is an important topic of how to induce weaknesses that are exploitable.

To win a superior ending it is often necessary to penetrate through a weakness with your King, but the defender can often guard a single weakness, or two weaknesses that are close together. You will often see an annotation "opening a second weakness" which is the way to exploit superior mobility.

Finally, I was once in a position to offer a draw to a much stronger player, IM Bill Hartston. Potentially I had a strong attack but could not regroup my pieces because I had to keep them tied down to defending a weak pawn. After we agreed the draw I mentioned this and Bill replied, "Ah yes, but Im tied down to attacking it" This remark is worth taking some time to understand.
> 1 votes

---
Tags: strategy, knights
---


# Question
Title: Does the MacBook chess game program not allow castling?
I have gotten back to learning chess, and I started using the chess game program on my 2015 MacBook Pro. Last night I wanted to castle, but it would not allow me to do so. I was white by the way. Later on, I saw that black was allowed to castle.

Is there some reason why the MacBook Pro Chess game program does not allow for castling? Or is there a rule about castling as white I am yet to learn?

I moved my King over to the Rook - nothing. I then moved my Rook over to the King, again nothing. The pieces went back to their original place.

# Answer
According to the rules of castling, you cannot castle if:

* Your king has ever moved.
* The rook you are castling with has ever moved.
* Your king is currently in check.
* Your king would be in check at the destination square.
* Your king must cross through check.

Most likely, one of these factors was the reason you couldn't castle.

If none of these are the case, then perhaps dropping the king on the rook is the problem. The program might want you to drop the king on its destination square.
> 9 votes

# Answer
I am going to accept DMs answer because it has so much good information on Chess rules, but to be clear my question was in regards to how does the MacBook Pro Chess game understand that you are trying to castle.

On my Windows 7 machine, you move the King to h1 and that's how it knows you are castling.

For future readers who run into similar problems where this does not work in their MacBook Pro Chess game, you need to move the King to g1 and at that point, your Macs Chess game understands you are castling and will move the Rook over to f1 for you.

At no point was I in check, so yes if you are in check, no attempt at castling will work. For Macs Chess game you cannot move the King to h1 where the Rook is, you have to move it to g1 to the left of the Rook and the Chess game will understand its castling and thereby move your Rook over to f1.

On Windows 7, the default behavior of the Chess game is you must move King over to h1 where the Rook is, it will understand it as castling and move the Rook over.
> 4 votes

---
Tags: software, castling
---


title: Pawn Sacrifice Justification

text:
# Question
Title: Pawn Sacrifice Justification
A few weeks ago, Magnus Carlsen (White) played against Anish Giri (Black), and this position was reached on the board on move 17 after black had played exf4:

Here is the full game:

```
[White "Magnus Carlsen"]
[Black "Anish Giri"]
[FEN ""]

1. c4 e5 2. Nc3 Nf6 3. Nf3 Nc6 4. g3 d5 5. cxd5 Nxd5 6. Bg2 Bc5 7. O-O O-O 8. d3 h6 9. Nxd5 Qxd5 10. a3 a5 11. Bd2 Qe612. Rc1 Qe7 13. Bc3 Nd4 14. e3 Nxf3+ 15. Qxf3 Bd6 16. Qh5 c617. f4 exf4 18. gxf4 Qxe3+ 19. Kh1 Rd8 20. Rce1 Qc5 21. f5 Bf822. Be4 Rd5 23. Rf3 b5 24. Rg1 Ra7 25. Bf6 g6 26. Qh3 Rd6 27. Qh4 Rxf6 28. Qxf6 Be7 29. Qxc6 Qxc6 30. Bxc6 Kg7 31. fxg6 fxg6 32. d4 a4 33. d5 b4 34. Be8 Bg5 35. h4 Bxh4 36. Rxg6+ Kh7 37. Rc6 Bg4 38. Rf4 Rg7 1-0

```

Now, with white to play, it would be natural would be to play exf4. However, gxf4 was played, hanging a pawn and letting black capture it with a check.

Can someone explain what is the logic behind such apparently wrong move?

# Answer
As was stated in the answer to this post made by D M, one idea of capturing in this manner is to open up the g-file for white's rooks to attack black's king. In the game this proved to be a very potent idea, and in general it's a good idea to open up lines for one's rooks against the enemy king if one intends to attack it.

But there is another point to letting the e-pawn hang and that is to gain some tempi for the attack. When black's queen spends one tempo on capturing on e3 with check, white responds by playing Kh1 (a move that white wants to make in order to clear the g-file for the rooks), so while black used a tempo to make a move that does nothing to bolster their defenses, white made a move that is crucial for the coming attack (gaining 1 tempo, relatively speaking). Next white improves the position of the rook on c1 by going to e1. Once again, this is done with a gain of tempo, since black's queen is exposed on e3 and needs to spend one tempo moving away. This way white manages to get two "free" tempi to make his position more ready for going on the attack while black had to strut around with their queen, arguably doing nothing to bolster their defenses.

So the pawn sacrifice had a two-fold purpose here, I would say. First, by capturing with the g-pawn white opens up an important line of attack against black's king. Secondly, by investing the e-pawn white gains some free tempi to use in order to make their position more ready to go on the offensive against black's king.

In general, material count is only one of many factors in evaluating a position, and while it may be the most obvious it is not always the most important one. In this example, Carlsen judged that his superior piece coordination and black's kingside weaknesses were more important positional factors than the material count, and seeing how the game went it is difficult to argue that his judgement was off.
> 10 votes

# Answer
It appears the reason was to clear the pawn from the g-file to get an attack on the opponent's king. Kh1 and Rg1 were later played, which supports this theory.
> 2 votes

---
Tags: tactics, middlegame, sacrifice, carlsen, master-games
---


# Question
Title: Has promotion with double check ever happened in a professional game?
Promotion is common in many games, and is sometimes comes with check. But something I have never seen in a game is a promotion that comes with double check like this example illustrates.

```
[FEN "8/3QPk2/8/8/8/8/8/8 w - - 0 1"]

1. e8=Q++

```

Has this ever occurred in a professional game? If so, has it happened for each type of promotion? An example that comes with checkmate would nice as well, but it has probably never happened.

# Answer
> 3 votes
Yes. I was able to locate a game between grandmasters which included a double-check promotion.

```
[Event "17. ch-EUR Indiv 2016"]
[Site "Gjakova KOS"]
[Date "2016.05.19"]
[Round "7.5"]
[White "Ter-Sahakyan, Samvel"]
[Black "Ponomariov, Ruslan"]
[Result "1-0"]
[WhiteElo "2601"]
[BlackElo "2715"]
[ECO "B51"]
[EventDate "2016.05.12"]
[WhiteTitle "GM"]
[BlackTitle "GM"]
[Opening "Sicilian"]
[Variation "Canal-Sokolsky (Nimzovich-Rossolimo, Moscow) attack"]
[WhiteFideId "13302531"]
[BlackFideId "14103320"]
[FEN ""]
[startply "102"]

1.e4 c5 2.Nf3 d6 3.Bb5+ Nd7 4.O-O a6 5.Bd3 Ngf6 6.Re1 b5 7.c4 g5 8.Nxg5
Ne5 9.Be2 bxc4 10.Nc3 Bh6 11.Nf3 Nd3 12.Bxd3 cxd3 13.e5 dxe5 14.Nxe5 Kf8
15.Qf3 Be6 16.Nxd3 Rg8 17.Ne5 Nd5 18.g3 Rc8 19.d3 Bg7 20.Bg5 f6 21.Ng6+
hxg6 22.Rxe6 Nb4 23.Be3 Kf7 24.Qe4 Qd7 25.Rb6 Rgd8 26.Rd1 Nxd3 27.Qc4+ Kf8
28.Rxa6 Qf5 29.Qe4 Qxe4 30.Nxe4 c4 31.Nc5 Nxc5 32.Rxd8+ Rxd8 33.Bxc5 f5
34.Ra4 Rd1+ 35.Kg2 Rc1 36.Rb4 Kf7 37.a4 c3 38.bxc3 Rxc3 39.Bb6 Ra3 40.a5
Bc3 41.Rb5 Ra2 42.h4 e5 43.Rc5 Bd4 44.Rc7+ Kf6 45.Rc6+ Kg7 46.Bxd4 exd4
47.a6 d3 48.Kf3 Kh6 49.Ke3 d2 50.Ke2 Kh5 51.Rf6 d1=Q+ 52.Kxd1 Rxf2 53.Kc1
Rg2 54.a7 Ra2 55.Rf7 Kg4 56.Kb1 Ra5 57.Rg7 Kxg3 58.h5 Rxa7 59.Rxa7 gxh5
60.Kc2 h4 61.Kd3 h3 62.Ke2 h2 63.Rg7+ Kh3 64.Rh7+ Kg2 65.Rg7+ Kh3 66.Kf2
h1=N+ 67.Kf3 Kh2 68.Rg2+ Kh3 69.Rg5 Kh2 70.Rxf5 Kg1 71.Rg5+ Kf1 72.Rg2 1-0

```

And here's one where the pawn is promoted to a rook:

```
[Event "2. London Chess Classic"]
[Site "London ENG"]
[Date "2010.12.14"]
[Round "6"]
[White "Kramnik, Vladimir"]
[Black "Carlsen, Magnus"]
[Result "1/2-1/2"]
[WhiteElo "2791"]
[BlackElo "2802"]
[ECO "D07"]
[EventDate "2010.12.06"]
[WhiteTitle "GM"]
[BlackTitle "GM"]
[Opening "QGD"]
[Variation "Chigorin defence"]
[WhiteFideId "4101588"]
[BlackFideId "1503014"]
[FEN ""]
[startply "113"]

1.d4 d5 2.c4 Nc6 3.Nf3 Bg4 4.Nc3 e6 5.Bf4 Bd6 6.Bg3 Nf6 7.e3 O-O 8.a3 Ne7
9.Qb3 b6 10.Ne5 c5 11.Nxg4 Nxg4 12.Rd1 Bxg3 13.hxg3 Nf6 14.cxd5 exd5 15.
Be2 Qd6 16.Qc2 h6 17.O-O c4 18.b3 Qxa3 19.bxc4 dxc4 20.Bf3 Rab8 21.Ra1 Qd6
22.Nb5 Qd7 23.Qxc4 a5 24.e4 Rfc8 25.Qe2 Rc6 26.Rab1 Rd8 27.Rfd1 Rdc8 28.d5
Rc2 29.Qe3 R2c5 30.Nd4 Re8 31.Qd3 Qd6 32.Qa6 Rb8 33.Nb3 Rc2 34.Nd4 Rc5 35.
Nb3 Rc2 36.Qd3 Rcc8 37.Nd2 Ng6 38.Be2 Qc5 39.Rb5 Qc3 40.f4 a4 41.e5 Nd7
42.Qxc3 Rxc3 43.Ne4 Rc7 44.Ra1 Ra7 45.d6 Ngf8 46.Nc3 Nc5 47.Nd5 Ra5 48.
Rxb6 Rxb6 49.Nxb6 Nfe6 50.Bc4 Kf8 51.f5 Nd8 52.Rf1 Ncb7 53.Re1 a3 54.e6
fxe6 55.fxe6 Nxd6 56.e7+ Ke8 57.exd8=R+ Kxd8 58.Rd1 Kc7 59.Ba2 Rg5 60.Nd5+
Kc6 61.Nc3 Rc5 62.Rxd6+ Kxd6 63.Ne4+ Kc6 64.Nxc5 Kxc5 65.Kf2 Kd4 66.Kf3
Kd3 67.g4 Kd2 68.Be6 Kd3 69.Kg3 Ke3 70.Kh4 Kf2 71.Bd5 g6 72.Kh3 g5 73.Kh2
Kf1 74.Be6 Kf2 75.Bc4 Ke3 76.Kg3 Kd4 77.Be6 Ke3 78.Kh2 Kf2 79.Bc4 Ke3 80.
Kg1 Kf4 81.Be6 Ke5 82.Bb3 Kf4 83.Be6 Ke5 84.Bb3 Kf4 85.Be6 Ke5 86.Bb3
1/2-1/2

```

And a bishop:

```
[Event "GMA"]
[Site "Bermuda BER"]
[Date "2003.02.02"]
[Round "8"]
[White "Markowski, Tomasz"]
[Black "Movsesian, Sergei"]
[Result "1-0"]
[WhiteElo "2574"]
[BlackElo "2663"]
[ECO "A09i"]
[EventDate "2003.01.25"]
[PlyCount "113"]
[FEN ""]
[startply "100"]

1.g3 d5 2.Nf3 g6 3.c4 d4 4.Bg2 Bg7 5.O-O c5 6.d3 Nc6 7.Na3 Nf6 8.Nc2 O-O
9.a3 a5 10.b3 e5 11.Rb1 e4 12.Ng5 exd3 13.exd3 Bg4 14.Qd2 h6 15.h3 Bf5 16.
Nf3 Qc8 17.Kh2 Nd7 18.Nh4 Be6 19.f4 Ne7 20.g4 Qc7 21.Kg1 f5 22.Qe2 Ra6 23.
Bd2 Bf6 24.g5 hxg5 25.fxg5 Be5 26.Nf3 Bg7 27.b4 axb4 28.axb4 Bf7 29.bxc5
Nc6 30.Rb5 Re8 31.Qf2 Ra2 32.Nfe1 Nde5 33.Qg3 Re7 34.Bf4 Qc8 35.Rb1 Ra5
36.Na1 Nd7 37.Nb3 Ra2 38.Rf2 Qa8 39.Nc2 Qa4 40.Qf3 Nde5 41.Qd1 Nxd3 42.
Qxd3 Bxc4 43.Qg3 d3 44.Ne3 Bxb3 45.Rxb3 Qxb3 46.Bd5+ Qxd5 47.Nxd5 Re1+ 48.
Kg2 Ree2 49.Rxe2 dxe2 50.Kf2 e1=B+ 51.Kxe1 Ra1+ 52.Kd2 Ra2+ 53.Kd1 Nd4 54.
Nf6+ Bxf6 55.gxf6 Ra1+ 56.Kd2 Ra2+ 57.Kd3 1-0

```

And a knight:

```
[Event "Lake Sevan GM"]
[Site "Martuni ARM"]
[Date "2010.07.11"]
[Round "1"]
[White "Grigoryan, Avetik"]
[Black "Petrosian, Tigran L"]
[Result "0-1"]
[WhiteElo "2584"]
[BlackElo "2597"]
[ECO "D30"]
[EventDate "2010.07.11"]
[FEN ""]
[startply "100"]

1.Nf3 d5 2.d4 c6 3.c4 Nf6 4.e3 e6 5.Bd3 Nbd7 6.Nbd2 dxc4 7.Nxc4 c5 8.O-O
Be7 9.e4 cxd4 10.e5 Nd5 11.Nxd4 Nc5 12.Bc2 O-O 13.a3 a5 14.Qg4 f5 15.Qg3
Qe8 16.Bg5 a4 17.Bxe7 Qxe7 18.Rfd1 Ne4 19.Bxe4 fxe4 20.Nd6 e3 21.fxe3 Bd7
22.Rac1 Bc6 23.h3 h6 24.Kh2 Kh7 25.Rf1 Nb6 26.Nxc6 bxc6 27.Rxf8 Rxf8 28.
Rxc6 Nd5 29.Qg4 Nxe3 30.Qe4+ Nf5 31.g4 Qh4 32.gxf5 Qf2+ 33.Qg2 Qf4+ 34.Kh1
exf5 35.e6 Qe5 36.Nc4 Qe1+ 37.Kh2 Rf6 38.Qg1 Qe4 39.Qg2 Qf4+ 40.Qg3 Qe4
41.Rc5 Rxe6 42.Qf2 f4 43.h4 f3 44.h5 Qg4 45.Qc2+ Re4 46.Nd6 f2 47.Rf5 Qg1+
48.Kh3 Qg4+ 49.Kh2 Re2 50.Qd3 f1=N+ 0-1

```

---
Tags: pawn-promotion, master-games, famous-games, double-check
---