Jyrki Heikkinen (1880) - Roger Watson (1800)

Diemer-Duhm Gambit, DDGA'96, 7.12.1996

1. e4 e6 2. d4 d5 3. c4 dxe4 4. Nc3 Bb4

4... Nf6 5. f3 Bb4 6. Be3 Bxc3+ 7. bxc3 O-O 8. Qc2 exf3 9. Nxf3 b6 10. Bd3 Bb7 11. Bg5 Bxf3?! 12. gxf3 Kh8 13. Qf2 Nbd7 14. Rg1 Qc8 15. Qh4 Rg8 (15... c5 16. Bxf6 Nxf6 17. Rxg7!!) 16. Rg3 h5 17. O-O-O c6? 18. Rh3 g6 (18... Re8 19. Bxf6 Nxf6 20. Qxf6!!) 19. Bxf6+ Nxf6 20. Qxf6+ Rg7 21. Rxh5+ 1-0, Heikkinen - Angus, DDGA 1996.

4... Nc6 5. Be3 f5 6. f3 Nf6 7. fxe4?? Ng4 8. Bf4 Qxd4, 0-1 in a few moves. Master Unes Hassim was lucky enough to win two games like this in the DDGA 1996.

5. Be3

In a booklet Blackmar Gemeinde (1956), Diemer gave two options: 5. Qa4+ Nc6 6. Be3 Bd7 7. Qc2 f5! and 5. Qb3!! Nc6 (5... c5 6. a3!! Bxc3+ 7. bxc3 cxd4 8. cxd4 Qxd4? 9. Bb2) 6. Be3 Nf6 7. O-O-O!.

5... Nf6 6. Qc2

6. g4!? c5 (6... Bxc3+ 7. bxc3 e5 8. h3) 7. g5 Nfd7 8. Bg2 is unclear.

6... Nc6

6... O-O 7. Ne2 b6 8. a3 Bxc3+ 9. Nxc3 Bb7 10. O-O-O Nbd7 11. Be2 Qe7 12. g4 Rfc8 13. g5 Ne8 14. Nxe4 c5 15. dxc5 Nxc5 16. Bxc5 Rxc5 17. h4 Bxe4 18. Qxe4 Rac8 19. Qd4 b5 20. Qd7 Qxd7 21. Rxd7 R5c7 22. Rxc7 Rxc7 23. b3 Kf8 24. Rd1 Ke7 25. Kb2 bxc4 26. Bxc4 Nd6 27. Bd3 g6 28. b4 Nf5 draw, Angus - Segerberg, DDGA 1996.

7. f3 O-O

7... Nxd4?! looked very tempting, but clearly it could only work in blitz. 8. Bxd4 Qxd4 9. Qa4+

• 9... Bd7 10. Qxb4 exf3 (10... e3 11. Rd1) 11. Nxf3 Qe3+ 12. Be2 Ng4 13. Nd1 +/-.
• 9... Nd7! 10. Qxb4 Nc5 11. Nb5 (11. Nxe4 Qe3+ 12. Kd1 Nxe4 13. fxe4 Bd7! unclear) Qe3+ 12. Kd1 Ke7 unclear or 12... O-O 13. Qd2 +/-.

8. O-O-O exf3 9. Nxf3

Naturally, 9. gxf3 could also be tried.

9... Bxc3

9... h6 10. h3 Bxc3 11. Qxc3 Qe7 12. Bd3 Rd8 13. g4 b5 14. g5 Nb4?! 15. gxf6 Nxa2+ 16. Kd2 Qxf6 17. Qb3 Qxf3 18. Qxa2 e5 19. d5 +/-, Erben - Heikkinen, DDGA 1996.

10. Qxc3

10. bxc3 Ng4 11. Bg5 f6 12. h3 fxg5 13. hxg4 h6? (13... g6 14. Qd2?! Rf4) 14. Rxh6! gxh6? 15. Qg6+ Kh8 16. Qxh6+ Kg8 17. Qg6+ Kh8 18. Bd3 mates.

10... h6

10... Ne4 11. Qc2 f5 looks safe.

11. Bd3 Ng4 12. Bg1 Bd7 13. h3 Nf6 14. g4 Nh7

Now White has clear advantage. 14... a5 15. g5?! (15. a3) Nb4 16. Bb1 Ne4! with good play.

15. Be3

No need to release the tension: White has plenty of time to develop the rest of the pieces.

• 15. Bxh7+ Kxh7 16. g5 hxg5 (16... h5!?) 17. h4 g4 18. Ng5+ Kg8 19. d5 exd5 20. Rxd5 with attack.
• 15. d5 exd5 16. cxd5 Ne7 gains nothing.

15... Ne7

15... f5 16. gxf5 exf5 17. d5 Ne7 18. Bxh6! gxh6 19. Rhg1+ Kf7 20. Rg7+ +-.

16. Qc2 f5

16... Nf6 is better.

17. Rhg1 g5

18. h4 Nc6

18... h5!? 19. gxh5 g4 20. Rxg4+ fxg4 21. Bxh7+ +/-.

19. a3 Qe7 20. gxf5

20. hxg5 f4 21. Bxh7+ Qxh7

• 22. g6 Qg7 23. Bf2 Be8 24. g5 h5 25. Nh4 +/=.
• 22. Qxh7+ Kxh7 23. Bd2 hxg5 24. Nxg5+ +/=.

20... exf5 21. Rde1 1-0

"That g-pawn seems to be my Achilles' heel. Every way I look at it, I either get mated or lose the queen", Watson wrote. A nice thriller that ended just before the action would have started.

• 21... Qg7 22. hxg5 h5 23. d5 Nd8 (23... Ne7? 24. Bd4) 24. Bd4 Qg6 25. Ne5 Qd5 26. c5 Qe7 27. g6 (or 27. Nf3) Nf6 28. Nf7 Ne4 29. Nh6#.
• 21... f4 22. hxg5 fxe3 (22... h5!?) 23. gxh6+ Kh8 24. Rg7 +-, but 22. Bd2 Qg7 23. d5 is even more crushing.
• 21... g4 22. Bxh6 Qf7 23. d5 Ne7 24. Ne5 Qe8 25. Rxg4+! fxg4 26. Bxh7+ Kh8 27. Bxf8 +-.

PGN version.