King and Pawn endings are very good practice for calculating variations.
Even the simplest looking endgames can contain difficulties.
In this week’s problem, the strong grandmaster playing Black, made a mistake and failed to find the win.
What is Black’s winning move?
In last Monday’s problem, White wins with 1. f4+! gxf4 2. Kf3! fxe3 3. fxe3 Kd5 4. Kf4 Ke6 5. e4 fxe4 6. Kxe4 and the endgame is a win.