Rook and pawn mate on the edge — Chess Library

The rook checks across the eighth rank while an advanced pawn controls h7 and Black’s g-pawn removes its own escape square.

Lesson

White to move. Main line: 1. Ra8#

Ra8# checks horizontally along the eighth rank and controls g8. The black king cannot capture a rook seven files away, and there is no black piece capable of interposing on the open rank.

The white pawn on g6 attacks h7, while Black’s pawn on g7 occupies the other adjacent square. With g8 controlled by the rook, all three flights around the h8 king have disappeared.

Advanced pawns often support mating nets without giving the check. Count their diagonal attacks and notice when an enemy pawn is a blocker rather than a shield; then a distant rook may supply the only missing line.