Chess Puzzle of the Week (181): Solution

Illingworth-Beeh, Ford Memorial 2002
White to play

Last week I asked you to analyse this pawn ending.

It might look at first as if White, with a passed pawn in the centre of the board, is pressing for a win, but in fact it’s Black who has more chances, although White can hold with careful play.

At some point in the near future Black will play f5, the f-pawn will be traded for White’s d-pawn, the black king will head for the queenside while the white king will head for the kingside. If both players promote, Black will be left with an extra pawn, which will win a pawn ending but only draw a queen ending. Races like this are common in pawn endings and have to be calculated accurately.

Stockfish 15 tells me White has three drawing moves, Ke4 (the simplest), a4 and h4, while all other moves, including the natural b4 which White, a very young junior at the time, chose in the game.

A couple of sample variations: you’ll see that Ke4! gives White an extra tempo to promote first, while after b4? Black will promote first and force a queen exchange.

1. Ke4! b5 2. h4 f5+ 3. gxf5 gxf5+ 4. Kxf5 Kxd5 5. Kg5 Kc4 6. Kh6 Kb3 7. Kxh7 Kxb2 8. h5 Kxa3 9. h6 b4 10. Kg6 b3 11. h7 b2 12. h8=Q b1=Q+ 13. Kg5 which is a tablebase draw.

1. b4? f5! 2. gxf5 gxf5 3. b5 f4 4. Ke4 f3 5. Kxf3 Kxd5 6. Kg4 Kc5 7. Kh5 Kxb5 8. Kh6 Ka4 9. Kxh7 Kxa3 10. h4 b5 11. h5 b4 12. h6 b3 13. Kg7 (or 13. Kg8 b2 14. h7 b1=Q 15. h8=Q Qb8+) 13… b2 14. h7
b1=Q 15. h8=Q Qa1+, trading queens and promoting the a-pawn.

Chess is hard. Pawn endings are hard, especially as you’ll probably have very little time on the clock when they appear on the board. It’s well worth your time looking at other possible variations in this fascinating endgame position.