Blunders in Chess

By Bill Wall


In 1994, Amatzia Avni published a book called Danger in Chess: How to Avoid Making Blunders.  The book offers chess players some guidance on how to avoid making blunders and how to develop an early warning system on the most dangerous moments in a chess game.

In chess, a blunder is a very bad move, like giving up a piece for nothing or allowing a checkmate in one or two moves.  It is a move which substantially decreased the player’s chances of winning.  It is usually caused by some tactical oversight due to carelessness, overconfidence, or fatigue.  The moves usually worsen the position by three pawns or more, or lead to a quick mate.

There is a difference between a blunder and a mistake or an inaccuracy.  The refutation of a blunder is usually something simple.  If you have to calculate a long variation to prove it is a blunder, then it is not a blunder.  It is a miscalculation.  Also, the resulting position of a blunder should be clear-cut.  If you can’t demonstrate a few moves after a blunder how bad the game is to a lower-rated player, then it is not a blunder.

An inaccuracy is not a blunder.  Inaccuracies are mainly positional moves such as swapping off the wrong color bishop, trading a good bishop for a bad knight, recapturing with the wrong pawn, not capitalizing on an open file, etc.

Blunders often occur because of a faulty thought process where a player does not consider the opponent’s forcing moves.  Every check, capture, and threat needs to be considered at each move.  Neglecting these possibilities leaves a player vulnerable to simple tactical errors.

There is a strong correlation between blunders and rating.  The highly-rated players blunder much less frequently than their lower-rated counterparts.

In chess, no one counts “advantages” or “winning positions.”  Only the final result matters.  You can build up a sizeable advantage and keep it during most of the game.  But it takes just a few seconds of a lack of attention to squander all your hard work and lose the game.  Bad blunders in chess can nullify all the former work you did to get an advantage.  Any chess move can be critical, and any decision may determine the outcome of the game.

Chess requires a great deal of concentration.  Stronger players manage to “know” (without concrete analysis of variations) when they can move quickly or when they need to take their time and utmost care to go into deep thought and re-examine the accuracy of former assessments.

Blunders or obvious dangers in chess include the following:

·        Leaving the king with insufficient support from other pieces

·        Weaknesses of the eighth rank (back rank mate possibility)

·        Entering a lasting pin

·        Capturing a “poisoned” pawn

·        Placing pieces without escape routes

·        Letting an enemy rook occupy the 7th rank

Common failures in sensing danger on the chess board include:

·        When the opponent plays badly in the opening (if he is playing weakly in the opening, he will probably play weakly throughout the game)

·        When the opponent plays incomprehensibly

·        When the opponent has an indifferent reputation (one tends to relax when playing supposedly weak opposition)

·        When the situation looks familiar (assuming the position is well-known or routine, when, in fact, it is not)

·        When there are almost no pieces left (the fewer the pieces, the less alert we are)

·        When moves are made that bring a false sense of security

·        Paying insufficient attention to the other side’s plans

·        Attacking without counting how may defenders are there

·        Neglecting defense while attacking

·        When victory is in sight

·        When the danger seems to be over

·        Too focused on attacking to see that your opponent has a stronger attack

·        Failed to evaluate a tactic that you thought your opponent could not find

·        Trying to play on a square you don’t control

·        Not seeing a discovered attack or that your opponent is preparing a fork

·        Overlooking king safety

·        Trying to play complex positions you don’t understand

·        Overlooking your opponent’s threat (you are asleep)

·        Overlooking your own threat (you are lazy)

·        Overlooking your opponent’s reply to your threat (you are over-excited)

·        Overlooking double attacks

Here are some ways to develop the skill of identifying dangers and recognizing critical moments on the chess board:

·        Adopt a paranoid approach

·        Maintain a self-critical attitude

·        Actively search for possible dangers

·        Think like your opponent as well.  Ask yourself, “What’s his plan?” or “Why did he do that?”

·        Implement a search for danger as a regular procedure

·        Study double-edged positions

·        Finish your line of thought with the best move of your opponent

·        Check every forcing reply

·        Search for the “killer” move to win the game, but for your opponent, not you.  That way, you can spot it and directed the game away from it.

The art of deception can be important in chess.  Some players, when they have known they have committed a blunder, get up and walk around happily, as if nothing is wrong.  Others will sit still and smile serenely.  If you are on the defensive, try to look completely dejected and uninterested, in the hope your opponent will get careless.  When you set a trap, try to look normal, or even to appear nervous.

Always question what looks like a blunder.  Grandmaster Lev Alburt’s advice is, “When your opponent makes a move that looks like an obvious blunder – especially if he is a pretty strong player – it is advisable to try to find out what ha has overlooked.”  Also, check twice to make sure that it is he who has overlooked something.  Don’t interpret your opponent’s move as meaningless.

If you want to avoid dumb blunders such as dropping a piece that you have left hanging, try taking a mental inventory of the position before you do anything else on each move.  Check which pieces are attacked and which pieces are hanging.  The brain will catalogue this pattern information in your head that act as a warning system against stupid errors.  However, the brain has a tendency to immediately want to investigate interesting lines and other moves.  The thought process will wander sometimes never to return to the original warning danger of a hanging piece.

Some top players practice bullet chess (1 to 2 minutes on the clock) to train their mind against blunders.  Bullet chess is all about seeing your opponent’s threats and dumb blunders.  It helps you familiarize with the pieces and how they move.  It helps you avoid blunders and helps you to see threats quickly.  Bullet chess also improves your ability to cope in time pressure, where most of the blunders happen. 


Here are some famous blunders:

Deep Fritz vs Vladimir Kramnik, 2006 – Kramnik overlooks getting mated in one move

Carlsen – Anand, game 6 of the 2014 world chess championship.  Carlsen played 26.Kd2? and Anand missed 26…Nxe5, winning.

Topalov – Kramnik 2006 – Topalov blunders with 32.Qg6, missing a win with 32.Rxg4+

Darga – Lengyel, 1964 – The GM resigns in a win position, missing 42.Rxe2 Bxh4+ 43.Ke3 (not 43.Kg2)

Carlsen – Shirov, Linares 2008 – Black blunders with his king after 79…Ke5??, allowing b8=Q+ and winning

Petrosian – Bronstein, Amsterdam 1956 – Petrosian hangs his queen

Bacrot – Inarkiev 2008 – another GM hangs his queen

Mamedyarov – Zagrebelny, 2004 – The GM hangs his rook

Christiansen – Karpov, 1993 – former world champion hangs two pieces

Reshevsky-Savon, 1973 – Reshevsky throws his queen away

Bronstein – Botvinnik, world ch match 1951 – Bronstein missed a draw with 57.Ne6+

Chandler – Z. Polgar, 1987 – Chandler takes a knight and draws, missing the win with 54.h4 instead of 54.gxh6