World champion Viswanathan Anand missed out on a chance to score a crucial victory and had to settle for a draw against challenger Veselin Topalov of Bulgaria in the ninth game of the World Chess Championship in Sofia on Thursday.
The players are locked 4.5-4.5 with just three more encounters remaining in the 12-game affair.
Anand, who blundered a drawn position in the eighth game, came back strongly and threatened to post his third victory in the match.
He had Topalov under pressure in the opening phase of the game but did not find the best manoeuvres to retain his advantage.
For the first time in the match, the Indian ace allowed Topalov the Nimzo Indian defense.
So far, all the games were fought in the Catalan opening and Anand attained two victories with that besides two draws.
However, following the seventh game, when Anand last played white in this match, the pundits had been predicting another change in Anand's guard, as Topalov reached a comfortable position.
This was what precisely happened.
Anand went for the Classical system, an opening played for ages at all levels, and the players followed on known theory till the 17th move.
The Indian was the first to show his new idea while Topalov treaded cautiously in the opening phase of the game. As a result, the Bulgarian had consumed close to 50 minutes by the time the new move was played by Anand.
The 'novelty' was in fact a knight retreat to which Topalov replied confidently but only a few moves later Anand was fighting for the initiative after parting his queens for two rooks.
The Bulgarian took an adventurous tour of his queen on the queen side to get some counter play and the stage was set for a spectacular finish.
Anand played his 38th move confidently, but when Topalov came up with his next move, the Indian missed out on his best manoeuvre to cause maximum trouble to his opponent.
As it happened in the game, Topalov crawled back in quick time and even after sacrificing his last remaining minor piece the local hero was still in the game, thanks to his double passed pawns on the queen side.
The game continued for a long time thereafter even though the outcome was hardly in any doubt. The longest game of the match so far was drawn after 83 moves.
With three games to come, it is advantage Topalov as he has two white games remaining.