Only one rook check wins — Chess Library

White has an extra pawn, but thirteen natural moves throw away the win. Syzygy tablebases prove that only one forcing rook check reaches a winning king-and-pawn ending.

Lesson

White to move. Main line: 1. Ra8+ Ke7 2. Rxf8 Kxf8 3. Kf6

1.Ra8+! is the only winning move. The check forces the black king onto the seventh rank, after which 2.Rxf8 exchanges the rooks under favorable conditions. Any quiet rook move or the immediate 1.b5 allows Black to draw.

The point appears after 2...Kxf8 3.Kf6!. White wins the opposition and escorts the b-pawn while the black king is one tempo too far away. Even here, pushing 3.b5? instead would draw, so the king move is part of the calculation.

This is a useful puzzle precisely because the first move looks like simplification rather than attack. In rook endings, calculate the pawn ending before agreeing to a trade: king position and move order matter more than the extra pawn by itself.