Parallel algorithms

丁立人 (Dīng Lìrén) – Richárd Rapport
Candidates Tournament 2022; Madrid, June 19, 2022
Grünfeld Defence D87

1. d4 Nf6 2. c4 g6 3. Nc3 d5 4. cxd5 Nxd5 5. e4 Nxc3 6. bxc3 Bg7 7. Bc4 c5 8. Ne2 Nc6 9. Be3 0-0 10. 0-0 b6 11. Rc1 Bb7 12. Bb5 Rc8 13. Qd2 cxd4 14. cxd4 Qd6 15. Rfd1 Qb4 16. Qd3 e6 17. h4 Rfd8

18. Bg5! A powerful novelty by 丁立人 (Dīng Lìrén), sensibly improving on 18. a3 Qe7 19. Bg5 Bf6 20. Qe3 h6 21. Bxh6 Nxd4 22. Rxc8 Nxe2+ 23. Bxe2 Bxc8 24. h5 Rxd1+ 25. Bxd1 Qd8 26. Bc2 Qc7 27. Bd1 Qd8 28. Bc2 Qc7 29. Bd1 Qd8 ½ : ½ Giri – Nepomniachtchi, The Magnus Carlsen Invitational, Prelims Tournament, chess24.com, April 23, 2020, match game 1 (time control: 15 minutes plus 10 seconds per move). 18. ... Nxd4!? Rapport comes up with a sharp Exchange sacrifice, rather than resigning himself to 18. ... f6 19. Bd2 (or also 19. Bf4) with the better game for White. 19. Bxd8 Rxd8 20. h5 Be5 21. a4 Kg7

22. Kf1! A strong, quiet move which neutralises all of Black’s tactics, while White also threatens to win a piece with Rc1-c4 (that was not playable right now: 22. Rc4?? Nf3+!). 22. ... Nxe2

23. Qxe2? This is a good mistake since it secures White a certain advantage, but 23. Qxd8! was much stronger, for after 23. ... Qxe4 (23. ... Nxc1 24. Qg5+−) 24. Bxe2 Qxg2+ 25. Ke1 Qh1+ 26. Kd2 Bf4+ 27. Kc3 Black is on the ropes. 23. ... Rxd1+ 24. Rxd1 a6. Of course taking the e4-Pawn at once would cost a piece. 25. Bxa6 Bxa6 26. Qxa6 Qxe4

27. Re1. Apparently, 丁立人 (Dīng Lìrén) is not yet himself — that is, his himself of three years ago. Here, for example, one can hardly disagree with the conclusions reached by the engines that 27. Qe2 is White’s best way to play for the win. 27. ... Qd4 28. Qe2 Bf6 29. hxg6 hxg6 30. Qe4 Qd2 31. Re2 Qd1+ 32. Re1 Qd2 33. g3 Bd4 34. Qe2 Qc3 35. Rd1 Qc6 36. Qg4 e5 37. Rxd4 exd4 38. Qxd4+ Kg8 39. Qd8+ Kg7 40. Qd4+ Kg8 ½ : ½.

An impossible synchronisation: just like two time zones existing in parallel. Photo: Stev Bonhage/FIDE.