Blunder (chess)

In chess, a blunder is a very bad move. It is usually caused by some tactical oversight, whether from time trouble, overconfidence or carelessness. While a blunder may seem like a stroke of luck for the opposing player, some chess players give their opponent plenty of opportunities to blunder.

What qualifies as a "blunder" rather than a normal mistake is somewhat subjective. A weak move from a novice player might be explained by the player's lack of skill, while the same move from a master might be called a blunder. In chess annotation, blunders are typically marked with a double question mark, "??", after the move.

Especially among amateur and novice players, blunders often occur because of a faulty thought process where they do not consider the opponent's forcing moves. In particular, checks, captures, and threats need to be considered at each move. Neglecting these possibilities leaves a player vulnerable to simple tactical errors.^[1]

One technique formerly recommended to avoid blunders was to write down the planned move on the scoresheet, then take one last look before making it.^[2][3] This practice was not uncommon even at the grandmaster level.^[4] However, in 2005 the International Chess Federation (FIDE) banned it, instead requiring that the move be made before being written down.^[5][6] The US Chess Federation also implemented this rule, effective as of January 1, 2007 (a change to rule 15A),^[7] although it is not universally enforced.

Grandmaster examples

Strong players, even grandmasters, occasionally make elementary blunders.

Mikhail Chigorin vs. Wilhelm Steinitz

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Mikhail Chigorin v. Wilhelm Steinitz, White to make his 32nd move

The position here was taken from Game 23 of the 1892 World Championship in Havana, Cuba. Chigorin is a piece up (Steinitz lost a knight earlier in the game) despite being a pawn down and his bishop being forced to stay on d6 to protect both the rook on e7 and the pawn on h2 from a possible mate. If he won, he would tie the match and send it to overtime. After 31...Rcd2, Chigorin played 32.Bb4??, a blunder thought by many as the greatest blunder ever in a World Championship. Steinitz replied with 32...Rxh2+, and Chigorin resigned the game immediately and lost the match. Otherwise, after 32...Rxh2+, the game would follow as 33.Kg1 Rdg2#.^[8]

Tigran Petrosian vs. David Bronstein

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Tigran Petrosian v. David Bronstein, White to make his 36th move

The position in the diagram here arose in the 1956 Candidates Tournament in Amsterdam. Petrosian, playing White, enjoys a clear advantage with strong knights, active rooks and plenty of mobility while Black's position is congested and hardly able to move. In fact Bronstein, playing Black, has for the last seven moves been making only apparently aimless knight moves, Nc6-d4-c6-d4, and now has played ...Nd4-f5, threatening White's queen, while White has been slowly strengthening his position. White can now easily preserve the positional advantage by a move like 36.Qc7, but overlooking that the queen was en prise, he played 36.Ng5?? and resigned after 36...Nxd6.

Miroslav Filip vs. Klaus Darga

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Miroslav Filip v. Klaus Darga, White to make his 33rd move

This game is taken from a 1961 tournament between Filip and Darga. Darga, playing Black, had a close mate coming up when he played 30...Bb7. However, Filip tried to keep the game alive with 31. Rc7+ Kg6 32. Qg8+ Kf5. On move 33, Filip could have kept the game alive with 33. g4+, which could have involved a queen exchange. But he blundered with 33. Qxh7+??, and Darga responded with 33...Kg4. Filip then resigned because he realized that there was no way he could stop Black's king from reaching the h3 square even if White played 34. Rc4+, Rg7+, Qg7+, or Qg6+. Either way if White played one of those four moves, the game would go on as 34...Kh3 35. Kf1 Qd1#.

Miguel Najdorf vs. Bobby Fischer

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Miguel Najdorf v. Bobby Fischer, Black to make his 30th move

This game between Miguel Najdorf and Bobby Fischer from the 1966 Piatigorsky Cup is an example where a player in a bad position breaks under the pressure. According to Mednis,^[9] Fischer's decisive error came earlier in the game and here the black pawn on f4 is about to fall. Fischer played the blunder 30...Nd6?? cutting the game short. After Najdorf played 31. Nxd6, Fischer resigned because he realized after Najdorf's response that 31...Qxd6 32.Nxb7 wins a piece because 32...Rxb7 33.Qc8+ is a fork which wins the rook on b7, so White wins at least a minor piece.

Najdorf commented on Black's 29...Rb8: "There is no satisfactory defense. If 29... Ba8 then 30. Nb6 or 30. Qf5 would win. ... I had to win minor material (the pawn at f5) but this [30... Nd6?] decides immediately. Fischer, demoralized because of his inferior position, did not notice the simple point."^[10]

Viktor Korchnoi vs. Anatoly Karpov

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Viktor Korchnoi v. Anatoly Karpov, White to make his 39th move

This position is from Game 17 of the 1978 World Championship between Viktor Korchnoi, the challenger and defector from the Soviet Union, and the World Champion, Anatoly Karpov. Karpov, playing Black, is hoping for a back rank mate with his rook with the possible move 39...Rc1#. However, Korchnoi could've prevented this by moving his g-pawn (but not the h-pawn because 39.h3 or h4 leads to 39...Rc1+ 40.Kh2 Nf1+ 41.Kg1 Nfg3+ 42.Kh2 Rh1#), providing an escape square for his king. Korchnoi did not notice Karpov's mate plan with his knights however, and played 39. Ra1??. It allowed a nice finish for Karpov, 39...Nf3!+, and Korchnoi resigned the game. Otherwise, the game would end as a result of the blunder as 40. gxf3 Rg6+ 41. Kh1 Nf2# or 40.Kh1 Nf2#. Karpov went on to win the match retaining the chess crown until he was defeated by Garry Kasparov in 1985. ^[11]

Murray Chandler vs. Susan Polgar

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Murray Chandler v. Susan Polgar, White to make his 54th move

In this example, from a tournament in Biel in 1987, the game would not result as a loss for the blunderer, but led to an embarrassing draw for the British GM Chandler. Susan Polgar has just played the wily trap 53...Ng8-h6!?, hoping to turn the game around. Chandler though, realizes that after 54.gxh6+ Kxh6 he will be left with the considerable material advantage of a rook pawn and bishop against a bare king. However, since the bishop is unable to control the promotion square h8, Black will draw if she is able to get her king to control h8 due to the wrong rook pawn fortress. But Chandler calculates further, and realizes that it is he who will win control over the h8 square after 55.Kf6, and thereby win the game.^[12]

Therefore Chandler played 54.gxh6+??, but instead of the expected 54...Kxh6 came 54...Kh8! This is in fact almost the same king, bishop, and rook pawn versus bare king situation as Chandler had calculated that he would avoid, and the small difference that White has two rook pawns rather than one has no effect on the result. Black controls the h8 square and cannot be chased or squeezed away from it, and so White cannot promote his pawn. After 55.Bd5 Kh7 56.Kf7 Kh8 the players agreed to a draw.

Chandler had numerous moves which would have maintained his winning position, the fastest according to the Shredder tablebase [1] are 54.h4 and 54.Bf5.

Garry Kasparov vs. Kiril Georgiev

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Garry Kasparov v. Kiril Georgiev, White to make his 78th move

This diagram is an example when the blunderer comes so close to winning that he/she makes a very bad move, drawing the game. In this blitz game, Kasparov, playing White, was just two moves away from a win (by 78. Qb4 Ka7 79. Qb7 mate) when he blundered with 78. Qc5??, placing Georgiev in a stalemate position.

Alexander Beliavsky vs. Leif Erlend Johannessen

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Alexander Beliavsky v. Leif Erlend Johannessen, White to make his 69th move

This example, from a game played in Linares in 2002, is one of the very rare circumstances where a grandmaster makes the worst move possible, the only one allowing checkmate on the next move. In this queen endgame, White has some advantage after 69.fxg6+ fxg6 70.Kf4 due to Black's weak pawn on c6. However, Beliavsky playing White played 69.Kf4??, overlooking the response 69...Qb8#. According to Johannessen, it took a few moments for both players to realize that it was checkmate, and Beliavsky was a good sport over this mishap.^[13]

Alexander Cherniaev vs. Stuart Conquest

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Alexander Cherniaev v. Stuart Conquest, Black to make his 87th move

This game was taken from a Hastings tournament from 2003-4. The position here looks a little drawish, with both sides trying to stop passed pawns from promoting. For the past three moves, Cherniaev pressured Conquest's king with 85.f6+ Kg6 86.Bd3+ Kf7 87.Nd6+. Conquest could've continued the game with 87...Kf8, providing a reasonable square to take over the promotion squares. However, he played 87...Ke6??, not noticing the response 88.Bf5#.

Deep Fritz vs. Vladimir Kramnik

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Deep Fritz v. Vladimir Kramnik, Black to make his 34th move

In November 2006, reigning World Chess Champion Vladimir Kramnik competed in the World Chess Challenge: Man vs. Machine, a six-game match against the chess computer Deep Fritz in Bonn, Germany. After the first game had ended in a draw, Kramnik, playing Black, was generally considered in a comfortable position in Game 2, and he thought so himself apparently, as he refused a draw by avoiding a potential threefold repetition on 29...Qa7. Kramnik's troubles began when he decided to play for a win and pushed his a-pawn, 31...a4. Commentators, including American grandmaster Yasser Seirawan, voiced concerns about Kramnik's intentions and the situation became more uncertain as the game went on with 32.Nxe6 Bxe3+ 33.Kh1 Bxc1 34.Nxf8, turning it into a likely draw.^[14] The game could have ended with 34...Kg8 35.Ng6 Bxb2 36.Qd5+ Kh7 37.Nf8+ Kh8 38.Ng6+.

However Kramnik's next move, 34...Qe3?? (a move which was awarded "???" originally, by ChessBase on a story covering Kramnik's blunder), came as a big surprise and was described as the possible "blunder of the century" by Susan Polgar, as Kramnik—incredibly—overlooked a mate in one.^[15] Deep Fritz immediately ended the game with 35.Qh7#, checkmate. Seirawan later called Kramnik's move "a tragedy."

ChessBase described the events as follows, "Kramnik played the move 34...Qe3 calmly, stood up, picked up his cup and was about to leave the stage to go to his rest room. At least one audio commentator also noticed nothing, while Fritz operator Mathias Feist kept glancing from the board to the screen and back, hardly able to believe that he had input the correct move. Fritz was displaying mate in one, and when Mathias executed it on the board Kramnik briefly grasped his forehead, took a seat to sign the score sheet and left for the press conference, which he dutifully attended."^[16] during which he stated that he had planned the supposedly winning move 34...Qe3 already when playing 29...Qa7, and had rechecked the line after each subsequent move. After an exchange of queens Black would win easily with his distant pawn; after 35.Qxb4 Qe2 or 35.Ng6+ Kh7 36.Nf8+ Kg8 black also wins eventually.

Chess journalist Alexander Roshal attempted to explain the blunder by saying that the mating pattern of a queen on h7 protected by a knight on f8 is extremely rare and not contained in a grandmaster's automatic repertoire.^[17]

Étienne Bacrot vs. Ernesto Inarkiev

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	a	b	c	d	e	f	g	h

Étienne Bacrot v. Ernesto Inarkiev, White to make his 23rd move

This game was played in May 2008 at the Baku Grand Prix from the FIDE Grand Prix 2008–2010. In round 11, Étienne Bacrot played White against Ernesto Inarkiev. On move 23, he checked the Black king with 23. Qe7+??. Both players calmly wrote down the move. Bacrot then realized that his Queen was under attack by the Black knight, and resigned.^[18]

Complete game scores of the examples

• Mikhail Chigorin v. Wilhelm Steinitz, Havana 1892
• Tigran Petrosian v. David Bronstein, Amsterdam 1956
• Alexander Beliavsky v. Leif Erlend Johannessen, Linares 2002
• Murray Chandler v. Susan Polgar, Biel 1987
• Alexander Cherniaev v. Stuart Conquest, Hastings 2003-4
• Deep Fritz v. Vladimir Kramnik, Bonn 2006 (chessbase.com)
• Viktor Korchnoi v. Anatoly Karpov, 1978
• Deep Fritz v. Vladimir Kramnik, 2006 (chessgames.com)
• Garry Kasparov v. Kiril Georgiev, 1988
• Miguel Najdorf v. Bobby Fischer, 1966
• Miroslav Filip v. Klaus Darga, 1961
• Étienne Bacrot v. Ernesto Inarkiev, 2008

See also

• Back rank checkmate
• Chess trap
• Chess blindness
• Kotov syndrome
• Swindle (chess)

References

1. ^ The principle of looking for checks, captures, and threats are repeated often by Dan Heisman, see e.g. Heisman, Dan (March 2002). "A Generic Thought Process". The Chess Cafe. http://www.chesscafe.com/text/heisman14.pdf. Retrieved 2 August 2010.  and Heisman, Dan (June 2006). "Is It Safe?". The Chess Cafe. http://www.chesscafe.com/text/heisman65.pdf. Retrieved 2 August 2010. 
2. ^ "When you have finished analyzing all the variations and gone along all the branches of the tree of analysis you must first of all write the move down on your score sheet, before you play it." Alexander Kotov, Think Like a Grandmaster, Chess Digest, 1971, pp. 73-74.
3. ^ Simon Webb, Chess for Tigers (3rd ed. 2005), pp. 121-22.
4. ^ Webb wrote of the practice, "You've seen other players doing it". Webb 2005, p. 121.
5. ^ FIDE Laws of Chess, see article 8.1 on recording of the moves
6. ^ The editors of Chess for Tigers noted that after author Webb had submitted his manuscript, "FIDE ... passed new laws forbidding a player to write moves down in advance and also insisting that a player's scoresheet be visible to the arbiter throughout the game". Webb 2005, p. 6.
7. ^ The United States Chess Federation
8. ^ http://www.chessgames.com/perl/chess.pl?tid=53817
9. ^ Mednis, Edmar. How to beat Bobby Fischer. 
10. ^ Kashdan, Isaac, ed. (1968), Second Piatigorsky Cup, Dover (1977 reprint), p. 93, ISBN 0-486-23572-6 
11. ^ Daniel King's Chess: From first move to checkmate
12. ^ Andrew Soltis, Chess to Enjoy in September 1997 Chess Life
13. ^ Johnsen, Sverre. "Find the Losing Move" (in 26 March 2008). http://sverreschesscorner.blogspot.com/2008/03/find-losing-move.html. Retrieved 17 August 2010. 
14. ^ Late game blunder costs Kramnik in loss to Deep Fritz chess software
15. ^ Blunder of the century, blog by Susan Polgar, 27 November 2006
16. ^ Man vs machine shocker: Kramnik allows mate in one
17. ^ How could Kramnik overlook the mate?, ChessBase News, 29 November 2006
18. ^ Baku R11: Wang Yue beats Svidler to join Grischuk, ChessBase News, 3 May 2008