Two Americans showed their mettle in recent scrimmage with top world players

The Tunisia Interzonal covered in our last column was a success for the Soviet contingent, which occupied four out of five top spots. The two US representatives, however, performed creditably. International Master Nick deFirmian of Oakland, Calif., finished ninth, with a plus score of 81/2-71/2. He was even in the running for a qualifying position until he overpressed and eventually came a cropper in a critical 13th-round game against Evgeny Ermenkov, a Bulgarian. His gamble was reasonable: Had he won, he would have finished in a fourth-place playoff tie with Soviets Viktor Gavrikov and Alexander Chernin for the last qualifying spot. The other American, IM Maxim Dlugy, of Kew Gardens, N.Y., at 19 the youngest player in the field, did a bit better, tying for sixth place with 9 points. Thus his surprise qualification for the Interzonal from last year's US Championship was no fluke.

In today's game we see him displaying a maturity that even a seasoned veteran might envy as he steers through a welter of snags to score against highly regarded Romanian grandmaster Mihai Suba. Modern Benoni Dlugy Suba Dlugy Suba Dlugy Suba Dlugy Suba Dlugy Suba Dlugy Suba

1. P-Q4 N-KB3

2. P-QB4 P-K3

3. N-KB3 P-B4

4. P-Q5 PxP

5. PxP P-Q3

6. N-B3 P-KN3

7. N-Q2 QN-Q2

8. P-K4 B-N2

9. B-K2 O-O 10. P-B4 R-K1 11. O-O P-B5 (a) 12. K-R1 (b) N-B4 13. P-K5 PxP 14. NxP P-K5 15. B-K3 N-Q6 16. BxN PxB 17. QxP P-QN4 (c) 18. NxP B-QR3 19. P-QR4 (d) NxP 20. BxP R-K2 21. B-B5 R-Q2 22. N-K5 BxN (K4) 23. PxB N-B5 24. Q-B4 P-N4 25. QR-K1 B-N2 26. RxN (e) B-Q4 27. Q-KB1 PxR 28. QxP B-K3 29. N-Q6 K-R1 30. R-K3 R-R4 31. B-N6 R-Q4 (f) 32. P-R3 Q-KB1 33. P-R5 P-B4 34. K-R2 R-KN2 35. R-KB3 R-Q8 36. R-B2 Q-R1 37. NxP R-KB2 38. Q-QR4 R-QN8 39. Q-B2 R-K8 40. Q-Q2 R-R8 41. N-R6 R-KN2 42. B-Q8 Resigns (g)

A. An aggressive bid for counterplay, even at the possible cost of a pawn.

B. 12. BxP, N-B4 yields Black excellent play. If 13. Q-B3, either 13. . . . N-N5 or 13. . . . B-N5 appears very promising, while 13. QB2, N-N5; 14. N-B3, Q-N3; 15. K-R1, BxN; 16. PxB, NxKP is disagreeable for White.

C. Black relied on this move, but he either overlooked or underestimated White's 19th and 20th moves.

D. Defends the knight, which, if captured, allows the White rook at R1 valuable play, X-raying in on R7.

E. This simplifying sacrifice illuminates White's advantage and eliminates Black's counterplay. With three pawns for the exchange, two of them connected and passed, White's victory is virtually assured.

F. If 31. . . . QxB; 32. Q-B6 ch, K-N1; 33. R-N3 ch, K-B1; 34. Q-R8 ch, K-K2; 35. Q-K8 mate, so Black tries for a back-rank mate.

G. As 43. B-B6 will be devastating.

International Grandmaster Arthur Bisguier is a former US champion and has won or shared the US Open title five times.