Alexandra Kosteniuk (Black) Puzzle: Pin — Win Material

A pin becomes especially powerful when the pinned piece is a queen and the king stands directly behind it. In this chess endgame, Black uses rook activity to align the enemy queen with its king, making the queen unable to move safely. The tactical point is not an immediate checkmate, but a decisive material gain: White must choose between preserving a minor piece and allowing the pinned queen to be captured.