THE GAME OF KINGS can have only one. Since Magnus Carlsen of Norway claimed the throne from Viswanathan Anand of India in 2013 he has successfully defended his World Champion title three times. He beat Mr Anand again in 2014, Sergey Karjakin, from Russia, in 2016, and Fabiano Caruana, an American, in 2018. In matches starting today, Mr Carlsen once again plays with his title on the line, facing Ian Nepomniachtchi, another Russian, across the board in Dubai. (The title defence, usually held every other year, was delayed last year because of the pandemic.)

Most think Mr Carlsen will fend off his challenger. His International Chess Federation Elo rating, often used to compare players’ skill, is currently 2,855, the highest of any player, and 73 points higher than Mr Nepomniachtchi’s 2,782. Indeed, by this metric, Mr Nepomniachtchi is only ranked fifth in the world. Last year, Mr Carlsen broke the record for the longest unbeaten streak in classical chess at the top level. He is the strong favourite according to bookmakers, with odds of 2/7.

Yet Mr Carlsen should be cautious. To compare the two players’ styles, The Economist collected data on tournament games between them and 43 other super-grandmasters (those rated above 2,700) since Mr Carlsen defended his title in 2018. We then counted the frequency at which moves were made to squares on the board for each. The movement of 152,176 pieces, in 1,594 games, suggest each player has different emphases. They also hint at where the fighting will be fiercest.

Mr Carlsen’s games feature heavier action on the queenside, especially in the c-file, as well as the third and sixth ranks. Mr Nepomniachtchi, in contrast, sees much more action in the centre. In part, this could reflect opening choices: Mr Nepomniachtchi is known for favouring so-called “hypermodern” variations, like the Grünfeld Defence, which see central pawns as targets for attack. (This being chess, hypermodern refers to the 1920s). This suggests more play on the queenside as a sign Mr Carlsen is doing well, even in games which eventually end in a draw.

Furthermore, though Mr Carlsen was the firm favourite against Mr Caruana in 2018, he needed a tie-breaker played under speed rules (where players are allotted less than one-quarter the thinking time) to prevail after 12 consecutive draws. Mr Nepomniachtchi also has a favourable head-to-head record against him in classical chess, and is known for his bold, daring tactics. In contrast, perhaps less bold but incredibly creative, Mr Carlsen is known for gradually and carefully building advantages from seemingly dead-even positions, inducing his opponents to make mistakes. In 2018, Messrs Carlsen and Caruana’s similarly careful styles made the contest a grind. This pairing, of clashing styles, promises more excitement. ■

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