World Champion Viswanathan Anand slipped to joint third spot after he was held to a draw by Levon Aronian of Armenia at the half way stage of the fourth Bilbao Final Masters.
Anand's third white in the tournament went in vain for the third time on the trot as the Indian ace could not use it to his advantage.
The Indian's sole victory in the event had come in the previous round when he beat Francisco Vallejo Pons of Spain.
World number one Magnus Carlsen of Norway rose back in contention for the top honour with a finely crafted victory over tournament leader Vassily Ivanchuk of Ukraine.
In the other game of the day, American Hikaru Nakamura scored his first win at the expense of Vallejo Pons.
With the Brazilian leg ending after the fifth round, the focus will now shift to Bilbao in Spain where the event will continue after a four-day break.
Despite his first loss, Ivanchuk still leads on 10 points in the soccer-like scoring system in place here.
Nakamura, who won his first game after four draws, occupies the second spot on seven points, while Anand, Aronian and Carlsen stand joint third now with six points each.
Pons is at the bottom on three points and one only wonders what his score might have been in this category-22 super tournament had Carlsen not blundered against him in a winning position.
Anand tried and got some advantage with his white pieces in the Closed Ruy Lopez against Aronian. The middle game had Anand pushing for more on the queen side and Aronian had no option but to go for the central breakthrough.
After regulation exchanges the players arrived at a rook and pawns endgame where Aronian had an extra pawn which was not of much use. The two agreed to a draw after 41 moves.