The Dos Hermanas tournament in Spain is poised for a tense finish, with half the field sharing first place after four rounds. Kramnik, Gelfand, Polgar, Salov and Anand have all scored three draws and one win to give them 21/2 points. Karpov and Topalov have 2 points, Short 11/2, Illescas and Shirov 1.

Nigel Short has made a good recovery, beating Illescas in round three and drawing with Anand in round four after making a disastrous start of two losses.

The most significant game so far, however, has been the defeat of Karpov by Kramnik in the third round. For the first 20 moves, nothing much seemed to happen. A quiet opening led to a position in which White had two bishops against bishop and knight, but it looked as if Karpov would have no difficulty in drawing the position.

The first sign that he might have some problems came after 26.e4. His 26...Nb8 was intended to counter the plan of Bc3 and Bb4, followed by e5, but Kramnik's 27.c5! left Black's pieces in an impossible tangle. 31.Ba4! and 32.Ba3! began an unusual attack that could not be met. At the end, 35...Rxa3 36.Nxa6 costs White a piece.

White: Vladimir Kramnik

Black: Anatoly Karpov

1 Nf3 Nf6 19 Rc1 Nd7

2 c4 e6 20 Ne1 Qa4

3 Nc3 Bb4 21 Qxa4 Rxa4

4 Qc2 0-0 22 f3 Nef6

5 a3 Bxc3 23 Bd1 Ra2

6 Qxc3 b6 24 Nd3 Kf8

7 b4 Bb7 25 Bb3 Ra8

8 Bb2 d6 26 e4 Nb8

9 e3 Nbd7 27 c5 bxc5

10 d4 Ne4 28 dxc5 dxc5

11 Qb3 a5 29 Nxc5 Bc8

12 Be2 axb4 30 e5 Ne8

13 axb4 Rxa1+ 31 Ba4 Nc7

14 Bxa1 Ndf6 32 Ba3 Kg8

15 0-0 Qd7 33 Ne4 Rxa4

16 b5 Ra8 34 Rxc7 Ba6

17 Bb2 c6 35 Nc5 resigns

18 bxc6 Qxc6