A look at how Hungarian underdog reached world semifinals

Of the four players still in contention in the World Championship candidates matches being played in London, Hungarian Grandmaster Zoltan Ribli is undoubtedly the one who has received the least recognition. Although he has been a successful grandmaster since 1973, until recently he has had to play second fiddle to his countryman Lajos Portisch. Now it would appear that Ribli is finally coming into his own.

In 1982 he dominated his zonal qualifying tournament and continued with another first place in the Interzonal at Las Palmas in the Canary Islands. In 1983 he placed second to Ulf Andersson in the superstrong Wijk aan Zee, Netherlands, tournament. Then he defeated Filipino star Eugenio Torre fairly easily in their quarterfinal candidates match.

Ribli, who is 32 years old, should be favored to beat Soviet Vassily Smyslov, a former world titlist who is now 62. But even if he is successful against Smyslov, his exploits will probably be overshadowed by the other semifinal between Gari Kasparov and Viktor Korchnoi, which is running concurrently.

It will be against the winner of that match that he should finally get his chance to prove he is of world championship caliber.

The fifth game from the Ribli-Torre match offers a fair view of Ribli's play. The opening variation is solid if uninspired. Black plays for a cramped but firm position and obtains the two bishops. When White vacillates with his Queenside counterplay, Black mounts a successful Kingside attack, based mainly on his control of the King Bishop file.

Semi-Slav Defense Torre Ribli 1. P-Q4 N-KB3 2. N-KB3 P-K3 3 P-B4 P-Q4 4. B-N5 P-KR3 (a) 5. BxN QxB 6. N-B3 P-B3 7. P-K3 N-Q2 8. B-Q3 Q-Q1 9. O-O B-K2 10. Q-K2 (b) O-O 11. KR-Q1 P-KB4 12. QR-N1 P-R3 13. P-QN4 B-Q3 14. P-QR4 N-B3 15. R(Q)-QB1 N-K5 16. Q-B2 B-Q2 17. P-N5 RPxP 18. RPxP Q-K2 19. P-B5 B-N1 20. PxP BxP 21. N-K2 Q-B3 22. B-N5 P-B5 23. NxP BxN 24. PxB QxBP 25. R-B1 (c) R-R6 26. R-N3 (d) BxB 27. RxR (e) BxR 28. KxB P-KN4 29. P-R3 (f) P-R4 30. R-R2 P-N5 31. PxP PxP 32. N-K5 Q-R7 33. P-B3 Q-R8 ch 34. K-K2 QxP ch 35. K-Q3 RxP ch 36. White resigns

A. Now White is forced to play 5. BxN, unless he is prepared to sacrifice a pawn with 5. B-R4, B-N5 ch; 6. N-B3 (or 6. QN-Q2), PxP, since 7. P-K4?, P-KN4 will cost White his King pawn and 7. P-K3, P-QN4 enables Black to hold the gambit pawn.

B. Either here or on the next move White is advised to play P-K4, which would yield him a spatial advantage.

C. It seems that White is definitely lost after this timid retreat. A pawn sacrifice with 25. BxB, PxB; 26. N-K5 was in order, since 26. . . . QxBP ch; 27. QxQ, RxQ; 28. R-R1 would pose Black great technical problems to score the win. Possibly White feared the murky 26. . . . N-Q7; 27. N-Q3, Q-N4; 28. P-B4, RxP; 29. NxR (not 29. QxN, R-B8 ch), NxR, 30. P-N3, N-R6; but here 31. Q-K2, to meet 31. . . . R-K1 with 32. Q-R6, appears to offer White fair chances.

D. Black threatened 26. . . . RxN and 27. . . . N-N4, winning.

E. If 27. RxB, then 27. . . . RxN as in previous note.

F. 27. P-N3, Q-B4, threatening 28. . . . NxP ch, as well as 28. . . . P-N5, is also dreadful.