Top seed Grandmaster P Harikrishna maintained sole lead in the third Marx Gyorgy Memorial International chess tournament with an easy draw against Hungarian GM Ferenc Berkes in the fourth round in Paks, Hungary.

On a day when two games provided results, Harikrishna's match was the only one that ended in a draw and even though defending champion Zoltan Almasi of Hungary came back to winning ways along with Ukraine's Zahar Efimenko, the Indian remained atop the tables with 3 points after four games.

With six rounds to come in the category-15 double round robin event, both Efimenko and Almasi trail Harikrishna on 2.5 points, while Wang Yue of China, who was comprehensively beaten by Almasi in the fourth round, and Berkes are joint fourth with two points apiece.

The nightmare of Peter Acs, a former Junior world champion like Harikrishna, continued as he lost his third game in four days going down to Efimenko.

Harikrishna achieved little with his white pieces against Berkes who played a solid defensive game in the Queen's gambit.

The Indian was forced to go along positional lines early in the game after Berkes came out with a slightly unusual third move by his Bishop and later transposed to a Tartakower defense game wherein Harikrishna could only get a minimal advantage.

The exchange of a few minor pieces followed by a firm control of the open queen file made Berkes' task easier and his offer of a draw after 24 moves was accepted by Harikrishna without much ado.

The day belonged to Almasi who showed his class against Wang Yue in a Sicilian Sveshnikov game where the former played white.

Getting along less trodden paths, Almasi went for a complicated and risky continuation in the opening with a piece sacrifice and his boldness was soon rewarded as Wang Yue chose a passive plan to combat the menacing white queen side pawns.

However hard the Chinese tried, the pawn march continued and when Wang Yue thought things were under control on the queen side, Alamsi turned his attention to the other flank to knock down a couple of more pawns.

The result was never in doubt from then on and Yue's resistance ended after 48 moves when Almasi successfully recovered his piece to get a won queen and pawns endgame.

Efimenko recorded his first victory at the expense of Peter Acs who is struggling with his form here. The Ukrainian was a bit lucky to get away with a shabby start that left Acs in command in the middle game.

However, the Hungarian failed to make the most of his opportunities and found himself in an endgame with an exchange less.

The final technicalities were handled by Efimenko in fine fashion and he romped home after 44 moves.

Results round 4: P Harikrishna (Ind, 3) drew with Ferenc Berkes (Hun, 2); Wang Yue (Chn, 2) lost to Zoltan Almasi (Hun, 2.5); Peter Acs (Hun, 0.5) lost to Zahar Efimenko (Ukr, 2.5).

The moves: (P Harirkishna vs Ferenc Berkes)

1. d4 d5 2. c4 e6 3. Nc3 Be7 4. Nf3 Nf6 5. Bg5 O-O 6. e3 h6 7. Bh4 b6 8. Bd3 dxc4 9. Bxc4 Bb7 10. O-O Nbd7 11. Qe2 Ne4 12. Nxe4 Bxe4 13. Bg3 Bd6 14. Rac1 Bxg3 15. hxg3 c5 16. dxc5 Nxc5 17. b4 Nd7 18. Ba6 Qe7 19. a3 Rfd8 20. Nd4 Nf6 21. f3 e5 22. Nc6 Bxc6 23. Rxc6 Rd7 24. Rfc1 Rad8 draw agreed

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