Queen versus pawn endgame

The chess endgame of a queen versus pawn (with both sides having no other pieces except the kings) is usually an easy win for the side with the queen. However, if the pawn has advanced to its seventh rank it has possibilities of reaching a draw, and there are some drawn positions with the pawn on the sixth rank. This endgame arises most often from a race of pawns to promote.

The side with the queen is the attacker and the side with the pawn the defender. Assume that the attacker has the move. If the pawn is not beyond its sixth rank, the attacker (to move) usually wins easily, but there are a few exceptions. The winning process is to either get the queen on a square in front of the pawn and getting the king over to help win the pawn or to check the defending king until it is forced in front of the pawn and using that tempo to bring the king closer, until it can assist in winning the pawn (Fine & Benko 2003:529). After the pawn is won, the attacker has an elementary checkmate (Seirawan 2003:49–53).

The queen usually wins easily if the pawn is on the sixth rank. In the first position, Black is to move, but White wins.

Exceptions can occur when the king blocks the queen on a file or diagonal, as in this position.

White needs to pin the pawn by 2. Qh8, but the king blocks the pin.

This was White's only check which prevents the pawn from advancing, and Black responds

repeating the position. If the white king is anywhere else (other than h7 and h8), the queen can pin the pawn and allow for the queen and then the king to approach (Fine & Benko 2003:530).

The biggest problem for a queen versus a pawn on the sixth rank is when its own king gets in the way. In this position, the white king prevents the queen from getting on the a1 to h8 diagonal, to pin the pawn to prevent it from advancing. White actually wins by:

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