Parimarjan Negi's title aspirations suffered a big setback as he lost the eighth and penultimate round of the Leiden International Chess tournament to David Howell of England.
After the shock defeat, Negi is in joint second spot with six points while Howell emerged as the sole leader with a full point lead over nearest rivals.
Giving Negi company on six points are Predrag Nikolic of Bosnia and Herzegovina, Benjamin Bok of Holland, Evgeny Vorobiov of Russia Bartosz Socko of Poland and compatriot S Arun Prasad.
Having done the hard work in last two rounds, a draw would have kept the Indian in excellent contention for winning the tournament.
Negi will face Benjamin Bok in the last round while Arun Prasad will take on Vorobiov and victory for the Indians would mean a podium finish.
The other Indian Grandmasters in the fray had good results. Arun Prasad played out an easy draw with top seed
Igor Khenkin of Germany while M R Lalith Babu and S Kidambi scored over Dutch duo of Etienne Goudriaan and Elwin Van der Auweraert respectively.
Lalith Babu moved to 5.5 points while Kidambi inched himself up to five points in all.
Negi faced the Ruy Lopez opening as black and it was a typically closed position in the middle game wherein Howell made some progress with a king side attack. Staying close to his guard, Negi neutralized white's initiative but in the process lost a pawn.
The position however still only slightly favoured Howell in the ensuing queen and minor piece endgame as Negi obtained counter play. However with the clock ticking away Negi transposed to a queen and pawns endgame after which Howell quickly set a trap to find the Indian unaware. The marathon game lasted 80 moves.
Arun Prasad did not have any difficulty in tackling Khenkin. The German Grandmaster got a central passed pawn in the middle game which was conveniently blocked and both decided not to take any undue risks.
Important results round 8 (Indians unless stated): David Howell (Eng, 7) beat Parimarjan Negi (6); Igor Khenkin (Ger, 5.5) drew with S Arun Prasad (6); Edwin Van Haastert (Ned, 5) lost to Predrag Nikolic (Bih, 6); Bartosz Socko (Pol, 6) beat Jan-Willem De Jong (Ned, 5); Evgeny Vorobiov (Rus, 6) beat Vladimir Zakhartsov (Rus, 5); Benjamin Bok (Ned, 6) beat Viacheslav Zakhartsov (Rus, 5); M R Lalith Babu (5.5) beat Etienne Goudriaan (Ned, 4.5): Csaba Horvath (Hun, 5.5) beat Alexander Van Beek (Ned, 4.5): John Van der Wiel (Ned, 5) drew with Sjef Rijnaarts (Ned, 5); Elwin Van der Auweraert (Ned, 4.5) lost to S Kidambi (5).