Soviet star improves on a 'book' move

Grandmaster Gari Kasparov, an aspirant to the world championship title, once again dominated a star-studded field when he placed first recently with an 11 -to-3 score at Niksic, Yugoslavia.

Kasparov, who comes from Baku in the Soviet Republic of Azerbaijan, has made a habit of this sort of thing since he startled the chess world by taking first place at Banja Luka, Yugoslavia, when he was barely 16. Now a mature 20-year-old , he continues to impress both by the margin of his victories and the quality of his creative, imaginative play. Although comparisons are often invidious, no less a pundit than Mikhail Botvinnik, world champion and iron strategist of the 1950s, has called Kasparov the best pupil he ever had. (Current world champion Anatoly Karpov was also his pupil.)

The following crushing victory over Hungarian Grandmaster Lajos Portisch from the Niksic event is typical and vintage Kasparov.

The game follows known theory for 14 moves. Then Kasparov innovates with a move that appears so natural and obvious that we wonder why we have not seen it before. In but a few more moves White's attack assumes irresistible proportions. It is likely that Portisch saw Kasparov's sacrifice on Move 21, but declining it would have allowed White similarly strong play without offering Black material compensation.

*2*Queen's Indian Defensem Kasparov Portisch 1. P-Q4 N-KB3 2. P-QB4 P-K3 3. N-KB3 P-QN3 4. N-B3 B-N2 5. P-QR3 P-Q4 6. PxP NxP 7. P-K3 NxN 8. PxN B-K2 9. B-N5+ P-B3 10. B-Q3 P-QB4 11. O-O N-B3 12. B-N2 R-QB1 3. Q-K2 O-O 14. QR-Q1 Q-B2 15. P-B4 (a) PxP 16. PxP N-R4 (b) 17. P-Q5 PxP (c) 18. PxP BxQP (d) 19. BxP+ KxB 20. RxB K-N1 (e) 21. BxP KxB 22. N-K5 (f) KR-Q1 23. Q-N4+ K-B1 24. Q-B5 P-B3 (g) 25. N-Q7+ RxN 26. RxR Q-B4 27. Q-R7 R-B2 28. Q-R8+ K-B2 29. R-Q3 N-B5 30. KR-Q1 N-K4 31. Q-R7+ K-K3 32. Q-N8+ K-B4 33. P-N4+ K-B5 34. R-Q4+ K-B6 35. Q-N3+ Black resigns.

A. An improvement over the ''book'' move, 15. P-K4, as it increases the mobility of the Queen Bishop without obstructing the King Bishop's diagonal.

B. Played both to attack the Bishop Pawn and to forestall White from playing Q-K4.

C. If 17. . . . NxP, 18. Q-K4 P-N3 19. BxN QxB 20. Q-K5 P-B3 21. QxP+ R-B2 22 . R-B1 Q-R3 23. P-Q6, and White is winning.

D. Results in the weakening of his King position and also allows the White Rook access to the King. Black is likely already lost, owing to the absence of defensive forces near his vulnerable King.

E. Allows a winning sacrifice, but other moves seem worse. If 20. . . . P-B3 21. Q-K4+ K-N1 (21. . . . P-N3 22. N-Q4) 22. N-R4 or 20. . . . P-N3 21. Q-K4 threatens 22. R-R5+ and 23. R-R8 mate.

F. Focuses on Q7 and allows the White Queen to infiltrate toward the Black King. Portisch puts up the sternest defense, as 22. . . . P-B4 23. R-Q7 Q-B4 24. N-Q3 is hopeless.

G. Here 24. . . . B-B3 allows 25. QxB RxR 26. N-N6+ K-K1 27. R-K1+, with a quick mate.