In chess, a smothered mate is a checkmate delivered by a knight in which the mated king is unable to move because it is completely surrounded (or smothered) by its own pieces, which a knight can jump over.
The mate is usually seen in a corner of the board, since only three pieces are needed to surround the king there, less than anywhere else.
The most common form of smothered mate is seen in the adjacent diagram.
The knight on f7 delivers mate to the king on h8, which is prevented from escaping the check by the rook on g8 and the pawns on g7 and h7.
Analogous mates on a1 and a8 are rarer because kingside castling is more common than queenside castling and brings the king closer to the corner.
For a smothered mate to occur in a game, it is usually necessary to sacrifice material to compel pieces to smother the king – a player is unlikely to voluntarily surround their king with pieces in a way that makes a smothered mate possible.
The technique is named after François-André Danican Philidor; this is something of a misnomer, however, as it is earlier described in Luis Ramirez Lucena's 1497 text on chess, Repetición de Amores e Arte de Axedrez,[1] which predates Philidor by several hundred years.
[2] An example is to be found in the game Jan Timman–Nigel Short at the 1990 Tilburg tournament.
[3] (Note that White would force mate even if his rook, and pawn on e7, were removed from the board, and Black had a knight on f6.
Occasionally, a smothered mate may be possible in the opening of a game.
One of the most famous, and most frequently occurring, is in the Budapest Gambit.
Note that the knight cannot be taken because the pawn on e2 is pinned to the white king by the black queen on e7.
Another notorious example is the so-called "Blackburne Shilling Gambit" (named after the 19th-century English player Joseph Henry Blackburne, supposedly because he used it to win shillings from amateurs).
This trap has occurred in many games, perhaps the earliest recorded example being Alekhine–Four Amateurs, simultaneous exhibition, Palma de Mallorca 1935.
An example of a similar smothered mate in master-level play is the game Edward Lasker–Israel Horowitz, New York City 1946, which went: 1. d4 Nf6 2.