Grandmaster Krishnan Sasikiran squandered several chances as GM Bartlomiej Macieja of Poland stretched their third round match to a tie-breaker in the World Chess Cup in Khanty Mansiysk (Russia [Images]).

After an easy draw with black in game one of this mini-match, Sasikiran misplayed a completely winning position in the second game and had to settle for a draw following tenacious play by Macieja.

The two will now progress to the tiebreaker stage where first two games will be played under rapid chess rules with 25 minutes to each player and a 10 second increment after every move is made.

If that fails to end the deadlock then the players will play two blitz games with 5 minutes and 5 second increment.

In case the they are still tied, there will be a final Armageddon game wherein white will get six minutes and white must win in order to proceed to the next round.

For the record, it was a Nimzo Indian defense by Macieja that led to a balanced endgame after routine exchange of pieces.

Just while it looked the players would sign peace, disaster struck Macieja and he simply overlooked a knight sortie that led to the demise a piece. 

Thereafter, there were only technical hurdles but an error-filled plan by Sasikiran enabled Macieja to exchange all the remaining four pawns on board and the resulting position was theoretically drawn.

Sasikiran, however, kept trying for a long time and it was only after 133 moves that he agreed to the draw.

Ivan Cheparinov of Bulgaria caused the biggest upset of the world cup when he knocked out second seed Shakhriyar Mamedyarov of Azerbaijan.

With a victory in the first game, all Cheparinov had to do was to hold his fort with black pieces in the return game and he did not disappoint his fans back home.

Top seed Vassily Ivanchuk of Ukraine was taken in to the breaker by Romanian GM Liviu-Dieter Nisipeanu. Ivanchuk failed to break the ice for the second time running and signed peace with white pieces in the second game.

Gata Kamsky of United States was one the prominent stars along with former World champion Ruslan Ponomariov of Ukraine an Magnus Carlsen of Norway who made it to the fourth round.

Kamksy needed just a draw against Kirili Georgiev of Bulgaria while Ponomariov and Carlsen defeated Evgeny Tomashevsky of Russia and Lenier Dominiguez of Cuba to achieve the feat.

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