Grandmaster Pendalya Harikrishna went down fighting against Hungarian GM Judit Polgar, the world's top woman chess player, and slipped to fifth spot in the Bilbao Blindfold World Cup in Bilbao, Spain, on Friday.
Harikrishna lost the first game of the two-game mini-match and later split points in the second game as he squandered chances in the middle game.
Chinese Bu Xiangzhi, meanwhile, continued with his dream run and defeated top seed and former World champion Veselin Topalov of Bulgaria 1.5-0.5.
Xiangzhi enhanced his lead to four points taking his tally to 12 points out of a possible 16 in this unique event that gives three points for a victory and one for a draw.
With three wins and three draws so far, Xiangzhi is now four points clear of nearest rivals Sergey Karjakin of Ukraine, Magnus Carlsen of Norway and Polgar who all have 8 points each.
Harikrishna is on six points and badly need victories in the remaining four games while Topalov is at the bottom of tables on five points thus far.
In the next round, Harikrishna meets Xiangzhi and will have to play out of his skin to stand a chance in his maiden Blindfold appearance.