India's Pendalya Harikrishna thrashed former World champion Veselin Topalov 1.5-0.5 to jump to joint second place after the fourth round at Bilbao Blindfold Chess World Cup in Bilbao, Spain.

After losing to Norwegian sensation Magnus Carlsen from a position of strength, it was an excellent comeback by Hari, who, after a victory and a draw, has five points in this unique event, where three points are awarded for victory and one for a draw.

Grandmaster Bu Xiangzhi, the lowest ranked player in the six-player double round-robin event, emerged sole leader on eight points after beating Carlsen 1.5-0.5. The Chinese player won the first game and drew the next to keep his slate clean.

Three points, or one victory behind Xinagzhi, is a group of Carlsen, Harikrishna and the world's youngest ever Grandmaster Sergey Karjakin of Ukraine.

Karjakin won one and drew one against the top-rated woman player Judit Polgar of Hungary, who now shares the last spot with Topalov on 4 points.

Harikrishna was a picture of confidence before the game.

"I had some apprehensions about playing blindfold before the first round, but after I played reasonably against Carlsen I thought I could play well in this variant too," Harikrishna said after the game.

Playing black in the first game, Harikrishna had his chances in the French defense but could not really convert his slightly better position in to a full point as Topalov put up stiff resistance.

"It was in the middle game that I thought I was better, but then I lost a pawn and had to find this perpetual check leading to a draw," said the Hyderabad-based Grandmaster.

It was in the second game that Topalov came under the firing line from the Indian star.

Playing white this time, Harikrishna went for complication by opting for a closed Sicilian and even though Topalov neutralised easily the nature of the position remained wild.

"He made a blunder when I got my counter play rolling, the position was quite interesting then," said Harikrishna.

In other matches of the day, Xiangzhi caused another flutter, beating Carlsen who played white in the first game. The Sicilian Najdorf came good for the Chinese as Carlsen made a couple of errors and lost in 68 moves.

In the return game, Carlsen tried to make amends but Xiangzhi proved quite solid in the Slav defense and drew comfortably.

Judit Polgar lost the second game after drawing the first against Karjakin. Polgar and Topalov are the two more experienced and older players in the event.

Results second day: P Harikrishna (Ind) beat Veselin Topalov (Bul) 1.5-0.5; Bu Xiangzhi (Chn) beat Magnus Carlsen (Nor) 1.5-0.5; Judit Polgar (Hun) lost to Sergey Karjakin (Ukr) 0.5-1.5.

Standings after round 4: 1. Xiangzhi 8 pts; 2-4: Harikrishna, Carlsen and Karjakin 5 each; 5-6: Polgar and Topalov 4 each.

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