Vishwanathan Anand and Judit Polgar were engaged in  another exciting game in the fourth round of the Mtel Masters Chess tournament in Sofia. Though more than two-thirds of their games have produced results, this one ended in a draw, but in a very unique fashion - with just the two kings left on the board.

It left Anand still in the tied second place with three others - Polgar, Vladimir Kramnik and Veselin Topalov. Michael Adams is the sole leader at 2.5 points, while Ruslan Ponmariov has 1.5 points.

In the other games today, Adams and Ponomariov drew in 27 moves, while home favourite Topalov and Kramnik, from whom he has taken over World No. 2 position - Anand being the No.1 after Kasparov's [Images] retirement - also drew their game by repetition after 56 moves.

Anand said he went all out for the win. "The full point was not there for the lack of trying. I did my best," said Anand of the fourth round game. "It was an interesting game and in the end it is not often you have a King v King situation. It is a rare situation, but I have seen it. In fact I have been in one of them, though I cannot remember," he added.

Anand and Polgar have mostly clashed in the Sicilian and in the Najdorf variation in particular. But this time though they were engaged in a Sicilian, it was in the Taimanov variation. "Today I didn't want to bore you guys with another Petroff," joked Anand when asked about it. On a more serious note, he said, "I tried, even though I felt she had a draw. It was very interesting."

They kept the crowd guessing till the very end, and then right at the end the Anand had a rook and bishop and one pawn to his rivals' rook and two pawns, one of them on the seventh rank poised for queening. The moves, which were slow till then, came at a rapid pace. The duo exchanged all the pieces and were left with just the king each on the board for an obvious draw.

Both Polgar and Anand love the Sicilian, which is suited to sharp players. Overall, almost two-thirds of their clashes have been in the Sicilian and seven of Polgar's eight wins have been in the Sicilian, while 13 of Anand's 20 wins have come in it.

Anand looked good for most part of the game, his 17th move of Qg5 looked particularly worrisome for Polgar who went into deep thought for almost half an hour. It had her queen trapped deep in. But she handled the situation well and held out for a draw.

Adams changed the move order right on the second move to limit Ponomariov's options as the latter tried to move into the Caro-Kann. "I wanted to limit his options in the opening," said Adams straight away after the game. And so he did in just 27 moves for the shortest game of the tournament.

Pairings for fifth round: Ponomariov - Topalov; Kramnik - Polgar; Anand - Adams

Results of fourth round: Ponomariov drew with Adams; Polgar v Anand; Topalov v Kramnik

Points after four rounds: 1. Adams 2.5 points; 2. Anand, Polgar, Kramnik and Topalov (2 points); 6. Ponomariov 1.5 point

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