Back rank checkmate
Encyclopedia
In chess
, a back-rank checkmate is a checkmate
delivered by a rook
or queen
along a back rank (that is, the row on which the pieces (not pawns) stand at the start of the game) in which the mated king
is unable to move up the board
because the king is blocked by friendly pieces (usually pawns) on the second rank . A typical position is shown to the right. It is also known as the corridor mate.
Back-rank mates are often guarded against simply by virtue of a friendly rook or queen protecting the back rank. However, it may be possible for the attacking side to deflect one of these pieces away from defensive duties. In the example shown to the left, for example, White to move can play 1.Qxc6 when black cannot reply 1...Rxc6 because of 2.Rd8+ Rxd8 3.Rxd8# with a back-rank mate. Black therefore loses his bishop
for no compensation-and Black has no good continuation because of the threat to chew up more material with Qxa8 or Qxc8. For example, 1...Qa6 2.Qxa8! Rxa8 3.Rd8+ Rxd8 4.Rxd8#. If Black tries to defend the back rank so that White's queen and bishop are skewered
, White can keep an extra piece, for example 1...b5 (defending d8 with the queen) 2.Qf3! keeping the rook on c8 stuck to the defense of the rook on a8, or 1...g6 (creating luft) 2.Qf6! and Black still can't take on pain of a back-rank mate. Examples such as this, where a rook cannot leave the back rank because of mate threats, are relatively common in chess.
Back-rank threats can be guarded against more permanently by moving one of the pawn
s in front of the king to give the king a flight square (such a move is sometimes said to "give the king some luft
"). If it were Black to play in the example to the left, he could counter White's threat with (among other moves) 1...g6, giving the king a square on g7 to which he could safely move. Note, however, that 1...h6 in this example would not do the job, as after the d3 rook moves the h7 square is guarded by the white bishop.
It is often not a good idea to play such pawn moves unless there is a pressing need to do so, as they can represent a loss of time. In many chess opening
s, however, they are often played for some other purpose, before any back-rank threats have emerged (...h6 is often played to bother a white bishop on g5, for example. Also see Fianchetto
).
's most famous games featured a variety of back-rank threats at the end. It was an exhibition game
played in Moscow
in 1914 against Ossip Bernstein
(Capablanca had the black pieces). The position shown to the right was reached after White's 29th move. Capablanca now played 29...Qb2! The simplest point is that 30.Qxb2 is not possible because of the back-rank mate 30...Rd1#, but there are several related ideas: for example, 30.Qe1, apparently defending the threatened rook, loses to 30...Qxc3 (if 31.Qxc3 then ...Rd1+ 32.Qe1 Rxe1#); 30.Rc2 fails to 30...Qb1+ 31.Qf1 Qxc2; and 30.Qc2 loses to 30...Qa1+ 31.Qc1 Rd1+ 32.Qxd1 Qxd1#, or 30...Qxc2 31.Rxc2 Rd1#. After 30.Rc8 it looks like white may turn the tables as 30...Rxc8? allows 31.Qxb2 to win a queen for a rook, however Capablanca has 30...Qa1+ (or Qb1+) when instead White loses a rook after 31.Qf1 Qxf1+ 32.Kxf1 Rxc8.
Note that had Capablanca played for the back-rank mate more directly with 29...Qb1+ 30.Qf1 Rd1?? (30...Qxa2 would be sensible), he would himself have lost to the back-rank mate 31.Rc8+ Rd8 32.Rxd8#.
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 back-rank checkmate is a 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...
delivered by a rook
Rook (chess)
A rook is a piece in the strategy board game of chess. Formerly the piece was called the castle, tower, marquess, rector, and comes...
or 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...
along a back rank (that is, the row on which the pieces (not pawns) stand at the start of the game) in which the mated 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...
is unable to move up the board
Chessboard
A chessboard is the type of checkerboard used in the board game chess, and consists of 64 squares arranged in two alternating colors...
because the king is blocked by friendly pieces (usually pawns) on the second rank . A typical position is shown to the right. It is also known as the corridor mate.
| Back-rank checkmates | |
|---|---|
Introduction
Back-rank mates occur quite often in games at fairly low levels, as it occurs out of carelessness. This is because beginners typically lack the skill to realize that such a fate could occur based on the laws of the game. At higher levels of play, though the mate itself does not occur very often, play is often affected by the possibility of it—the fact that a player has to spend time guarding against the mate may leave him vulnerable to other tactical ideas.Back-rank mates are often guarded against simply by virtue of a friendly rook or queen protecting the back rank. However, it may be possible for the attacking side to deflect one of these pieces away from defensive duties. In the example shown to the left, for example, White to move can play 1.Qxc6 when black cannot reply 1...Rxc6 because of 2.Rd8+ Rxd8 3.Rxd8# with a back-rank mate. Black therefore loses his bishop
Bishop (chess)
A bishop is a piece in the board game of chess. Each player begins the game with two bishops. One starts between the king's knight and the king, the other between the queen's knight and the queen...
for no compensation-and Black has no good continuation because of the threat to chew up more material with Qxa8 or Qxc8. For example, 1...Qa6 2.Qxa8! Rxa8 3.Rd8+ Rxd8 4.Rxd8#. If Black tries to defend the back rank so that White's queen and bishop are skewered
Skewer (chess)
In chess, a skewer is an attack upon two pieces in a line and is similar to a pin. In fact, a skewer is sometimes described as a "reverse pin"; the difference is that in a skewer, the more valuable piece is in front of the piece of lesser or equal value...
, White can keep an extra piece, for example 1...b5 (defending d8 with the queen) 2.Qf3! keeping the rook on c8 stuck to the defense of the rook on a8, or 1...g6 (creating luft) 2.Qf6! and Black still can't take on pain of a back-rank mate. Examples such as this, where a rook cannot leave the back rank because of mate threats, are relatively common in chess.
Back-rank threats can be guarded against more permanently by moving one 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...
s in front of the king to give the king a flight square (such a move is sometimes said to "give the king some luft
Luft
Luft, the German word for "air" , is used by some chess writers and commentators to denote a space left by a pawn move into which a castled king may move, especially such a space made with the intention of avoiding a back rank checkmate. A move leaving such a space is often said to "give the king...
"). If it were Black to play in the example to the left, he could counter White's threat with (among other moves) 1...g6, giving the king a square on g7 to which he could safely move. Note, however, that 1...h6 in this example would not do the job, as after the d3 rook moves the h7 square is guarded by the white bishop.
It is often not a good idea to play such pawn moves unless there is a pressing need to do so, as they can represent a loss of time. In many chess opening
Chess opening
A chess opening is the group of initial moves of a chess game. Recognized sequences of opening moves are referred to as openings as initiated by White or defenses, as created in reply by Black. There are many dozens of different openings, and hundreds of named variants. The Oxford Companion to...
s, however, they are often played for some other purpose, before any back-rank threats have emerged (...h6 is often played to bother a white bishop on g5, for example. Also see Fianchetto
Fianchetto
In chess the fianchetto is a pattern of development wherein a bishop is developed to the second rank of the adjacent knight file, the knight pawn having been moved one or two squares forward....
).
Example from game by Capablanca
One of José Raúl CapablancaJosé Raúl Capablanca
José Raúl Capablanca y Graupera was a Cuban chess player who was world chess champion from 1921 to 1927. One of the greatest players of all time, he was renowned for his exceptional endgame skill and speed of play...
's most famous games featured a variety of back-rank threats at the end. It was an exhibition game
Exhibition game
An exhibition game is a sporting event in which there is no competitive value of any significant kind to any competitor regardless of the outcome of the competition...
played in Moscow
Moscow
Moscow is the capital, the most populous city, and the most populous federal subject of Russia. The city is a major political, economic, cultural, scientific, religious, financial, educational, and transportation centre of Russia and the continent...
in 1914 against Ossip Bernstein
Ossip Bernstein
Ossip Samoilovich Bernstein was a Russian chess grandmaster and a financial lawyer.-Biography:...
(Capablanca had the black pieces). The position shown to the right was reached after White's 29th move. Capablanca now played 29...Qb2! The simplest point is that 30.Qxb2 is not possible because of the back-rank mate 30...Rd1#, but there are several related ideas: for example, 30.Qe1, apparently defending the threatened rook, loses to 30...Qxc3 (if 31.Qxc3 then ...Rd1+ 32.Qe1 Rxe1#); 30.Rc2 fails to 30...Qb1+ 31.Qf1 Qxc2; and 30.Qc2 loses to 30...Qa1+ 31.Qc1 Rd1+ 32.Qxd1 Qxd1#, or 30...Qxc2 31.Rxc2 Rd1#. After 30.Rc8 it looks like white may turn the tables as 30...Rxc8? allows 31.Qxb2 to win a queen for a rook, however Capablanca has 30...Qa1+ (or Qb1+) when instead White loses a rook after 31.Qf1 Qxf1+ 32.Kxf1 Rxc8.
Note that had Capablanca played for the back-rank mate more directly with 29...Qb1+ 30.Qf1 Rd1?? (30...Qxa2 would be sensible), he would himself have lost to the back-rank mate 31.Rc8+ Rd8 32.Rxd8#.