Cross-check
Encyclopedia
This article is about a type of move in chess
Chess
Chess is a two-player board game played on a chessboard, a square-checkered board with 64 squares arranged in an eight-by-eight grid. It is one of the world's most popular games, played by millions of people worldwide at home, in clubs, online, by correspondence, and in tournaments.Each player...

. Cross checking is also a penalty in ice hockey.


In chess
Chess
Chess is a two-player board game played on a chessboard, a square-checkered board with 64 squares arranged in an eight-by-eight grid. It is one of the world's most popular games, played by millions of people worldwide at home, in clubs, online, by correspondence, and in tournaments.Each player...

, a cross-check is a tactic in which a check played in response to a check, especially when the original check is blocked by a piece
Chess piece
Chess pieces or chessmen are the pieces deployed on a chessboard to play the game of chess. The pieces vary in abilities, giving them different values in the game...

 that itself either delivers check or reveals a discovered check from another piece. Sometimes the term is extended to cover cases in which the king
King (chess)
In chess, the king is the most important piece. The object of the game is to trap the opponent's king so that its escape is not possible . If a player's king is threatened with capture, it is said to be in check, and the player must remove the threat of capture on the next move. If this cannot be...

 moves out of check and reveals a discovered check from another piece (this is also known as a royal check); it does not generally apply to cases where the original checking piece is captured.

The cross-check is an essential tactic in winning some endgames such as those with two queens
Queen (chess)
The queen is the most powerful piece in the game of chess, able to move any number of squares vertically, horizontally, or diagonally. Each player starts the game with one queen, placed in the middle of the first rank next to the king. With the chessboard oriented correctly, the white queen starts...

 versus one or a queen and pawn versus a queen
Queen and pawn versus queen endgame
The queen and pawn versus queen endgame is a chess endgame in which both sides have a queen and one side has a pawn, which he is trying to promote. It is very complicated and difficult to play. Cross-checks are often used as a device to win the game by forcing the exchange of queens...

. In these cases, the defense usually tries for a perpetual check
Perpetual check
In the game of chess, perpetual check is a situation in which one player can force a draw by an unending series of checks. Such a situation typically arises when the player who is checking cannot deliver checkmate; while failing to continue the series of checks gives the opponent at least a chance...

 and sometimes the stronger side can stop it only by a cross-check.

Examples

A Cross-check occurs from time to time in games. It is an essential tactic
Chess tactic
In chess, a tactic refers to a sequence of moves which limits the opponent's options and may result in tangible gain. Tactics are usually contrasted with strategy, in which advantages take longer to be realized, and the opponent is less constrained in responding.The fundamental building blocks of...

 in winning endgames such as two queens
Queen (chess)
The queen is the most powerful piece in the game of chess, able to move any number of squares vertically, horizontally, or diagonally. Each player starts the game with one queen, placed in the middle of the first rank next to the king. With the chessboard oriented correctly, the white queen starts...

 versus one queen, or queen and pawn
Pawn (chess)
The pawn is the most numerous and weakest piece in the game of chess, historically representing infantry, or more particularly armed peasants or pikemen. Each player begins the game with eight pawns, one on each square of the rank immediately in front of the other pieces...

 versus queen, where it is used to stop a series of checks from the opponent and force the exchange
Exchange (chess)
In the tactics and strategy in the board game of chess, an exchange or trade of chess pieces is series of closely related moves, typically sequential, in which the two players capture each others pieces. Any types of pieces except the kings may possibly be exchanged, i. e. captured in an...

 of queens. It is also used in some chess problem
Chess problem
A chess problem, also called a chess composition, is a puzzle set by somebody using chess pieces on a chess board, that presents the solver with a particular task to be achieved. For instance, a position might be given with the instruction that White is to move first, and checkmate Black in two...

s.

Botvinnik vs. Minev game

Cross-checks are rare in actual play, though they do occur, and in some endgames, particularly queen
Queen (chess)
The queen is the most powerful piece in the game of chess, able to move any number of squares vertically, horizontally, or diagonally. Each player starts the game with one queen, placed in the middle of the first rank next to the king. With the chessboard oriented correctly, the white queen starts...

 endgames, they are very important. The position shown to the right is the final position in the famous queen endgame from the game between Mikhail Botvinnik
Mikhail Botvinnik
Mikhail Moiseyevich Botvinnik, Ph.D. was a Soviet and Russian International Grandmaster and three-time World Chess Champion. Working as an electrical engineer and computer scientist at the same time, he was one of the very few famous chess players who achieved distinction in another career while...

 and Nikolay Minev
Nikolay Minev
Nikolay Nikolaev Minev was born in Rousse, Bulgaria, on 8 November 1931. He is a chess International master and noted chess author....

, Amsterdam Olympiad, 1954. In the position shown, after 91. Kc5!!, Black resigned because the promising looking checks 91...Qc7+, 91...Qg1+, 91...Qf2+ and 91...Qc2+ are answered by the cross-checks 92.Qc6+, 92.Qd4+, 92.Qd4+ and 92.Qc4+ respectively, forcing an exchange of queens in all cases, which will result in the promotion
Promotion (chess)
Promotion is a chess rule describing the transformation of a pawn that reaches its eighth rank into the player's choice of a queen, knight, rook, or bishop of the same color . The new piece replaces the pawn on the same square and is part of the move. Promotion is not limited to pieces that have...

 of the pawn
Pawn (chess)
The pawn is the most numerous and weakest piece in the game of chess, historically representing infantry, or more particularly armed peasants or pikemen. Each player begins the game with eight pawns, one on each square of the rank immediately in front of the other pieces...

 and winning the game by a basic checkmate
Checkmate
Checkmate is a situation in chess in which one player's king is threatened with capture and there is no way to meet that threat. Or, simply put, the king is under direct attack and cannot avoid being captured...

. This is an important theme in queen endgames: the weaker side often gives a series of checks, and it is frequently important for them to avoid simplifying cross-checks such as these in reply , . If the black queen attacks the pawn instead of checking it does no good since the promotion square of the pawn is protected by its queen.

Two queens versus one

In the position on the left from Botvinnik-Ravinsky, Black resigned. With best play according to the endgame tablebase
Endgame tablebase
An endgame tablebase is a computerized database that contains precalculated exhaustive analysis of a chess endgame position. It is typically used by a computer chess engine during play, or by a human or computer that is retrospectively analysing a game that has already been played.The tablebase...

, 126...Kb3 127.Qf7+ Ka4 128.g8=Q Qg4+ 129.Kh6 Qh4+ 130.Kg7 Qg3+ 131.Kf8 Qd6+ 132.Qe7 Qh6+ 133.Qgg7 Qf4+ 134.Qgf7 Qb8+ and the position on the right is reached. Then the cross-check 135.Qee8+ (or Qfe8+) forks
Fork (chess)
In chess, a fork is a tactic that uses a single piece to attack multiple pieces at the same time. The attacker usually hopes to gain material by capturing one of the opponent's pieces. The defender often finds himself in a difficult position in which he cannot counter all threats. The attacking...

 the king and queen, forces an exchange, and wins the game.

Anderson problem, 1919

Cross-checks are relatively infrequent in actual play, but are popular in chess problem
Chess problem
A chess problem, also called a chess composition, is a puzzle set by somebody using chess pieces on a chess board, that presents the solver with a particular task to be achieved. For instance, a position might be given with the instruction that White is to move first, and checkmate Black in two...

s since they make for a relatively unobvious solution. In the problem shown to the right, white is to move and mate in two moves against any defence. It is by G.F. Anderson and was first published in Il Secolo in 1919. The key 1.Kd6, threatening 2.Qb7#, gives the black king two flight square
Flight square
In chess, a flight square or escape square is a safe place or a square to which a King or other piece can move if it is threatened. A bishop sometimes begins to get hemmed in after Morphy's defense is used, and thus pawn to c3 may be used to create an extra escape square.One way to get a king out...

s, and two of the variations exploit these: 1...Kb6 2.Bc2# and 1...Kb4 2.Kxc6#. The other two defences exploit the fact that the key exposes the white king to checks, and are answered by cross-checks: 1...Rg6+ 2.Be6# and 1...Rd3+ 2.Bd5#.

Anderson problem, 1961

The problem to the right, also by G.F. Anderson (first published in The Observer
The Observer
The Observer is a British newspaper, published on Sundays. In the same place on the political spectrum as its daily sister paper The Guardian, which acquired it in 1993, it takes a liberal or social democratic line on most issues. It is the world's oldest Sunday newspaper.-Origins:The first issue,...

in 1961) and also a mate in two, features no less than five cross-checks. The key is 1.Qb6 (threat: 2.Ne4#), with the following variations:
1...exf6+ 2.Nb7#
1...exd6+ 2.Nd7#
1...Nd4+ 2.Rf5#
1...Nxd6+ 2.Nd3#
1...Nf-other+ 2.Ne4#
1...Kxf6 2.Qb2#
1...Kxd6 2.Rd4#


Further reading

  • John Rice, Chess Wizardry: The New ABC of Chess Problems (London, Batsford, 1996)

External links

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