World Junior champion P Harikrishna suffered an unexpected defeat against Grandmaster Ruben Felgaer of Argentina in the fourth round of category-16 Dos Hermanas International Chess in Spain on Tuesday.

The loss proved quite costly for Harikrishna as from his overnight joint second spot, the Indian was relegated to joint seventh position in the standing list.

Ukrainian wonderboy Sergey Karjakin continued to be atop the tables after agreeing for a draw with former champion Alexander Rustemov of Russia [Images].

Karjakin, who took his tally to 3 points out of a possible 4, is now followed by Teimour Radjabov of Azerbaijan and Felgaer, who both have 2.5 points apiece while Zurab Azmaiparashvili of Georgia, and Russian trio of top seed Alexey Dreev, Oleg Korneev and Rustemov were another half point adrift.

Harikrishna was next in line along with Spaniard Miguel Illescas Cordoba and Lenier Dominguez was at the bottom of the tables with just one point in his kitty.

Five more rounds remain in this Euros 16000 prize tournament being played on a double round-robin basis between ten players.

Choosing the Ivan's gambit with his white pieces, Felgaer was in command right from the opening. Harikrishna felt the heat once his king side was paralysed and his pieces did not get much air to breath. Slow tightening of noose ensued thereafter and Harikrishna had no hopes of revival. Losing an exchange mid-way, Harikrishna called it a day in 33 moves.

If Ruben showed a lot of heart, Radjabov was not far behind in cruising past Cordoba who suffered his second successive loss in the event. It was a Benoni defence in which Cordoba went haywire from an innocuous position trying to equalise quickly.

As it happened in the game, Cordoba's bid never materialise as Radjabov got his passed pawn rolling on the queen side that won him a piece. The game lasted 43 moves.

It was not such a dull day even though the customary draws were there as usual. Karjakin could not do much despite playing white against Rustemov after the latter, as black, employed the Petroff defence.

The players fought a well-analysed variation for sometime before reaching a balanced middle gam e where the draw was agreed to in 27 moves.

Alexei Dreev yet again played the longest game of the day without much success. Up against Korneev, the top seed faced the Queen's Gambit declined playing white but failed to get anything more than a miniscule advantage. Quick exchanges led to a rook and pawns endagme where even an extra pawn fair led to deliver the goods for Dreev. Draw was agreed in 76 moves.

In the other game of the day, Azmaiparashvili was his content self against Dominguez in a Caro Kann defence. After a flurry of exchanges, the Georgian sacrificed a piece to get perpetual checks in the 33 mover.

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