With Vassily Ivanchuk and Magnus Carlsen [Images] eyeing his numero uno tag, World champion Viswanathan Anand [Images], his pre-tournament favourite tag notwithstanding, just cannot afford to lower his guard in the Grand Slam Chess Final Masters starting in Bilbao, Spain, on Monday.

With a winner's purse of Euro 1,50,000 dangled before them, Anand will be joined by Magnus Carlsen of Norway, Vassily Ivanchuk of Ukraine, Levon Aronian of Armenia, Veselin Topalov of Bulgaria and Teimour Radjabov of Azerbaijan in the double-round-robin tournament where each plays another twice with alternate colours.

A major first is the new point system under which a win will be awarded with three points, a draw with one point and no points for a loss.

To discourage short draws, players are forbidden to talk to each other during the game or offer draws. In case a position is a draw, it will be decided by the Chief Arbiter.

According to the average ratings of the participants, the event surpasses all with a staggering 2775.63 rating average and is category 22 tournament according to FIDE charts.

For the first time ever in the world an event of such magnitude will take place in the street, in the Plaza Nueva, right in the centre of Bilbao's Old Town.

While Anand (2798, according to July ratings) starts as the rating favourite, he is also under threat to lose is number-one slot in ratings as both Ivanchuk (2781) and Carlsen (2775) are within striking distance of the Indian who next plays a world championship match with Vladimir Kramnik [Images] of Russia [Images].

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