Anatoly Karpov finally remembered that he is the world champion and scored his first win at Wijk aan Zee at the expense of Judit Polgar. His best hope now, however, seems to be to scratch his way to the relative respectability of a 50 per cent score - but he will need another win from his last three games to achieve even that modest objective.

At the top end of the table, Viswanathan Anand maintained his lead with a comfortable win over Friso Nijboer. His closest rival is now Alexei Shirov, who moved into second place with a win over Jan Timman. Full scores after round 10: Anand 7; Shirov 61/2; Kramnik 6; Adams, Timman, Polgar, Gelfand and Topalov 51/2; Karpov and Piket 41/2; Salov, van der Sterren, Nijboer and van Wely 31/2.

Anand's latest win was the product of excellent opening preparation. The idea of meeting 11...h6 with 12.h4 is an old one in this variation of the Sicilian. Black cannot capture the bishop on g5 without exposing his king to a mating attack down the h-file. White's 15.e5, however, gave Black the chance to grab the piece and survive. 17...Rxc3! was the key move; after 18.bxc3 Nd5 19.Qh3 (19.Rxd5 exd5 leaves the black bishop guarding h3) 19...Nxc3+ 20.Kc1 (20.Kb2 Qa3+ leads to mate) 20...Nxe2+ 21.Kb1 Qb4+ 22.Ka1 Qc3+ wins for Black. As the game went, Nijboer never quite had enough attack for his sacrifice.

White: Friso Nijboer

Black: Viswanathan Anand

1 e4 c5 20 Qh3 Nh6

2 Nf3 d6 21 gxh6 Qxe5

3 d4 cxd4 22 Rde1 Qg5

4 Nxd4 Nf6 23 hxg7 Qxg7

5 Nc3 Nc6 24 Re3 Bg5

6 Bg5 e6 25 Rg3 f6

7 Qd2 Be7 26 Qg4 Kf7

8 0-0-0 0-0 27 Qd4 Qg8

9 f4 Nxd4 28 Qe4 Bc6

10 Qxd4 Qa5 29 Rh7+ Ke8

11 Kb1 h6 30 Qh4 Qg6

12 h4 Rd8 31 Qh3 Rd6

13 Be2 Bd7 32 a3 Kd8

14 Qe3 Rac8 33 Ka1 Qf5

15 e5 dxe5 34 Qh1 Bd7

16 fxe5 hxg5 35 d4 Rc6

17 hxg5 Rxc3 36 Qh2 e5

18 Bd3 Rxd3 White resigned

19 cxd3 Ng4