Queen and pawn versus queen endgame

Müller & Lamprecht, diagram 9.12A
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8
8
77
66
55
44
33
22
11
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White to play wins; Black to play draws

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 one tries 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. It is almost always a draw if the defending king is in front of the pawn.

Karsten Müller and Frank Lamprecht say that this endgame occurs quite frequently but Mark Dvoretsky says that it occurs quite seldom. This is the second most common "piece and pawn versus piece" endgame, next to the rook and pawn versus rook endgame.