World chess champion Garry Kasparov regained control of his title defense against Anatoly Karpov with a powerful performance in the 18th game of their match Saturday.

Kasparov adjourned by sealing his 41st move in an envelope to end the five-hour playing session.The champion had the advantage of an extra pawn and the more active position, and experts unanimously predicted that Karpov should lose the game.

Kasparov had looked worn and subdued as play began in Lyon's Palais de Congres, with little sign of the boundless nervous energy which is his trademark.

The overall score was tied at 8 1/2 to 8 1/2 with two wins and 13 draws each.

The game was to resume Sunday. Kasparov needs only a 12-12 tie in the 24-game series to retain the crown.

Here are the moves Saturday:

Kasparov Karpov

White Black

1. e4 e5

2. Nf3 Nc6

3. Bb5 a6

4. Ba4 Nf6

5. 0-0 Be7

6. Re1 b5

7. Bb3 d6

8. c3 0-0

9. h3 Nd7

10. d4 Bf6

11. a4 Bb7

12. Ka3 exd4

13. cxd4 Kb6

14. Bf4 bxa4

15. Bxa4 Kxa4

16. Qxa4 a5

17. Bd2 Re8

18. d5 Nb4

19. Bxb4 axb4

20. Qxb4 Rb8

Kasparov Karpov

White Black

21. Qc4 Qc8

22. Kd4 Ba6

23. Qc3 c5

24. dxc6 Bxd4

25. Qxd4 Qxc6

26. b4 h6

27. Re3 Re6

28. f3 Tc8

29. Rb3 Bb5

30. Rb2 Qb7

31. Nc2 Qe7

32. Qf2 Rg6

33. Ne3 Qe5

34. Rbb1 Bd7

35. Ra5 Qe7

36. Ra7 Qd8

37. Nd5 Kh7

38. Kh2 Rb8

39. f4 Re6

40. Qd4 Qe8