This is from Leonard Barden,
How to Play the Endgame in Chess (1975), diagram 122, page 75.
1. f4! exf4 Quote:Giving up a pawn to try and keep the position blocked. If 1... Bf6 white has the typical break-through 2. fxe5 dxe5 3. c5! bxc5 4. b6! and wins. 1... Kd7 might be tried, although 2. c5 still looks strong.
2. gxf4 Kd7 3. Bxd4 Kc7 4. Bc3 Kd7 5. Bb4 Kc7 6. Ke3
... 22. Kd5 Resigns I think after 1.f4 Bf6 2.fxe5 Bxe5! black can draw: 3. Bxd4 Bxd4! 4. Kxd4 Kd8 5. Ke3 Ke7 6. Kf3 Kf7 with the opposition. It's not every day you can improve on GM adjournment analysis, so I looked into it ... and found that the diagram position never happened in the game. I sourced it from the 1974 yearbook, but also ChessBase and chessgames.com agree with my source. Here is the actual game position:
39. f4 exf4 40. gxf4 Ke8 41. Kxd4 Kd7 42. Kd3 Kc7 43. Ke3 reaching the same position as after Barden's 6.Ke3. In the actual game 39...Bf6 is clearly impossible, 39...Kd7 even more so.
On chessgames.com, GIAaron asked on 2015.05.26:
Quote:I could be wrong, but maybe 50...bc draws. I can't get White to win
any of the lines which result from an eventual b6, followed by
trading the h4 pawn for the f4 pawn. I could be missing something,
of course. (p/) Does anyone know any way White can force a win
there?
Below is my attempt to show a win for white after 50...bxc5 (or 12...bxc5 from the above diagram). Position 1 is just a typical situation after b5-b6 and the exchange of pawns. Positions A,B,C are the same except for the location of the black king on a8,b8,c8 respectively.
1. f4 exf4 2. gxf4 Ke8 3. Kxd4 Kd7 4. Kd3 Kc7 5. Ke3 Bf6 6. Kf3 h4
7. Ke3 Bg7 8. Kd3 Bf6 9. Bd2 Kd7 10. Be3 Kc7 11. Bf2 Kc8 12. c5 12... bxc5!? 13. Be1 Kb8 (13... Kc7 14. Ba5+ Kc8 15. Kc4 (
or 15. b6) 15... Kb8 16. b6 axb6 17. Bxb6 see "position 1" in bold 17th move)
14. Kc4 (14. Ba5 is also good. 14... Kc8
(
14... Bb2!? Black should probably try this. At least there is a chance for white to go wrong. 15. Bd8 (15. Kd2?! Bf6 16. Kd3 (16. b6? axb6 17. Bxb6 c4 =) 16... Bb2 17. Bd8)
15... Bc1 16. Bxh4 Bxf4 17. Bf6 Be5 18. Bxe5 dxe5 19. d6 +-)
15. b6
(
or 15. Kc4 transposing back to 14.Kc4)
15... axb6 16. Bxb6 Kb8
(
16... Bb2 17. a7 Kb7 18. Bc7 Kxa7 19. Bxd6 Ba3 20. Kc4 Kb6 21. Be7) (
16... Bg7 17. Bd8 Bh6 18. Bg5) (
16... Be7 17. Kc4 Bf6)
17. Kc4 see "position 1" in bold 17th move)
14... Kc8 (14... Ka8 15. Ba5 Bb2?! 16. Bc7 +- there will not be stalemate 16... Bf6 17. Bxd6 Be5 18. fxe5 (or 18. Bxc5))
15. Ba5 Kb8 (15... Bb2 is very similar to 14.Ba5 Bb2: 16. Bd8 Bc1 17. Bxh4 Bxf4 18. Bf6 Bg3
(
18... Be3 19. h4 f4 20. Bg5) (
18... Be5 19. Bxe5 dxe5 20. d6 f4 21. b6 f3 22. b7+ Kb8 23. d7) (
18... Kc7 19. h4 Kb6 20. Bd8 mate)
19. h4 f4 20. h5 f3 21. Kd3 c4+ 22. Ke3 Be5
(
22... Bf4+ 23. Kxf3)
23. Bxe5 dxe5 24. h6 +- (or 24. Kxf3 +-))
16. b6 axb6 17. Bxb6 "position 1"
17... Ka8 (17... Bb2 18. a7+ Kb7 19. Bc7)
(17... Bg7 18. Bd8 Bh6 19. Bg5)
(17... Be7 18. Kb5 Bf6 19. Ba5)
(17... Kc8 18. Kb5 Kb8 19. Ba5 Kc8?!
"position C", the worst of the three for black...
(
19... Ka8 see "position A" in the bold 19th move 20. Kc6) (
19... Bb2 20. a7+ Kxa7 21. Bc7) (
19... Ka7 20. Bc7 Be7 21. Bb6+ Kb8 22. Ba5 Bf6 is "position B" in the note to bold 22nd move 23. Kc6)
20. Kc6 Kb8 white is a tempo up on "position B" 21. Kxd6 c4 22. Ke6 +-)
18. Bc7 (18. Kb5 is also good.)
18... Be7 19. Ba5 (Or 19. Kb5. I make these bishop moves instead to show that white does not need to make "only" moves in order to win.)
19... Bf6 (19... Ka7 20. Kb5 Bf6 simply transposes.
(
20... c4? 21. Bb6+ Ka8 22. Kxc4))
20. Kb5 (20. Bb6 Kb8 21. Kb5 Ka8
(
21... Kc8 22. Kc6 Kb8 23. Kxd6 c4 24. Ke6)
22. Bc7 Be7 23. Ba5 Bf6 see "position A" in the bold 23rd move 24. Kc6)
20... Ka7 (20... Kb8 see "position B" in the note to bold 22nd move 21. Kc6)
21. Bc7 Be7 22. Bb6+ Ka8 (22... Kb8 23. Ba5 Bf6
"position B"
24. Kc6 c4 25. Kxd6 c3 26. Ke6 c2
27. Bd2 Bb2 28. d6 c1=Q 29. Bxc1 Bxc1 30. d7 Kc7 31. Ke7 +-)
23. Ba5 Bf6 "position A"
24. Kc6 c4 25. Kxd6 c3 26. Ke6 (26. Kc7? c2 27. Bd2 Bb2 28. d6 c1=Q+ 29. Bxc1 Bxc1 30. d7 Bxf4+ -+)
26... c2 27. Bd2 Bb2 28. d6 c1=Q 29. Bxc1 Bxc1 30. d7 +-