Chunking in patterns of GM thought

This game features two nice examples of the role of experience in GM thought: one, where he drew on a remembered example (Vukovic), and another where extraneous information from an analogous type of position (Winawer) led to mistakes in thinking.

Nunn,J (2605) - Korchnoi (2615) (11)

Amber-blind, 1994

1. e4 c6 2. d4 d5 3. e5 Bf5 4. Nf3 e6 5. Be2 c5 6. O-O Nc6 7. c3 Rc8 8. a3 h6 9. b4 c4 10. a4 Nge7 11. Na3 Ng6 12. Nc2 Nh4 13. Ne3 Nxf3+ 14. Bxf3 Bd3 15. Be2 Bxe2 16. Qxe2 h5 17. f4 g6 18. g3 Ne7 19. Ng2 Nf5 20. Ne1 Kd7 21. Nf3 Be7 22. Ba3 Qf8 23. Ra2 Kc7 24. Rfa1 Qh6 25. Bc1 Kb8 26. b5 Rce8 27. Ng5 Qg7 28. Ba3 Bd8 29. a5 f6 30. Nf3 Qd7 31. exf6 Bxf6 32. Rb1 Ka8 33. Bc5 Qh7 34. Rba1 Rhg8

 

j+-+t+t+
Xx+-+-+d
-+-+xLx+
PpBx+s+x
-+xP-P-+
+-P-+nP-
r+-+q+-P
R-+-+-K-

Black has the threat ...g5. How can White open a file against the King?

  a5-a6 is met by ...b6; b5-b6 by ...a6. Nunn, playing blindfold here, recalled reading Vukovic [see Canon attack: opening lines], and came up with:

35. Bb6 a6

[35... g5 36. a6 axb6 37. axb7+ Kb8 38. Ra8+ Kc7 39. Rc8+ Rxc8 40. bxc8=Q+ Kxc8 41. Qxe6+]

[35... Rg7 36. a6 axb6 37. axb7+ Kxb7 38. Ra7+ Kc8 39. Ra8+ Kd7 40. R1a7+ Kd6 41. Qe5+ Bxe5 42. fxe5#]

[35... Nd6 36. a6 axb6 37. axb7+ Kb8 38. Ra8+ Kc7 39. b8=Q+ Rxb8 40. R8a7+ Rb7 41. Qxe6 Rf8 42. Qxd5 Qd7 43. Ne5 Bxe5 44. fxe5]

[35... Kb8 36. a6 axb6 37. axb7 Qxb7 38. Ne5 Ne7 39. Nd7+ Qxd7 40. Ra8+ Kc7 41. R1a7+ Kd6 42. Qe5+ Bxe5 43. fxe5#]

36. bxa6 bxa6

 

j+-+t+t+
+-+-+-+d
xB-+xLx+
P-+x+s+x
-+xP-P-+
+-P-+nP-
r+-+q+-P
R-+-+-K-

37. Rb2

[37. Rb1 Nunn says he nearly played this move, because the position reminded him of a Winawer French when there is a Pawn on c2. Fortunately he analysed a line with Qe2-b2 when the pawn on c2 vanished and the danger from h7 re-appeared!]

37... g5 38. fxg5 Bxg5 39. Nxg5

Rxg5 40. Bc5 h4 41. Rb6 1-0

  "I had to resign one move before you had to resign!" -- KORCHNOI

[41... Qa7 42. Rxe6 Rxe6 43. Qxe6 Qb7 44. Rf1 hxg3 45. h4 42. Rxa6+ Kb8 43. Qb2+ Kc8 44. Ra8+ Kc7 45. Qb6+ Kd7 46. Qb7#]

1-0

Chess Quotes

"Nimzovitch became then for me more or less the author of the only book which could help me get away from these Euwe books, which, I admit, are very good for the ordinary club player. But once you've reached a certain strength you get the impression that everything that Euwe writes is a lie."
— Bent LARSEN, in KEENE, Nimzowitsch: a reappraisal.

  I still like them! - DrD