Chess and boxing seem as bizarre a pairing as anything, but they do have something in common, writes David Edmonds.

One is a duel often characterised by cruelty, ruthlessness and violence. And boxing is much the same.

The former world heavyweight champion, Lennox Lewis, is now more likely to be seen hunched over the chess board than in the boxing ring. Yet the very idea that boxers might play chess, and vice versa, strikes many people as incongruous.

Chess after all, is the ultimate cerebral sport - boxing the most nakedly brutal. When his chess opponents discover he used to box, Lennox says, they're convinced they'll whip him. "And when I beat them, they're upset."

Find out more Image copyright Thinkstock David Edmonds is a chess writer and co-author of Bobby Fischer Goes To War. Dominic Lawson interviews Lennox Lewis over a game of chess as part of the series, Across The Board on BBC Radio 4 at 13:45 GMT on 1 January 2014 Or catch up on BBC iPlayer

He's not the only chess-playing boxer. Lewis successfully defended his title against the Ukrainian Vitali Klitschko. Klitschko holds a PhD and has entered Ukrainian politics. Like his brother, Wladimir, another boxing champion, Klitschko is a keen chess player.

Lewis jokes that he wants a promoter to put on a chess match between him and his old rival - though it seems unlikely that any chess bout would command the multimillion dollar purse they fought over in 2003.

The weirdness of combining boxing and chess - brain and brawn - has been used to attract spectators to a new sport, "chess boxing." It sounds like something from Alice in Wonderland.

In chess boxing the two combatants have alternating rounds of chess and boxing, victory achieved in several ways but most clearly by a checkmate or a knockout.

Image copyright Reuters Image caption Chernobayev of Belarus competes against India"s Shaliesh at chess... Image copyright Reuters Image caption ... boxing previous slide next slide

After trying to bash and bruise each other around the face and body, the opponents remove a single glove and continue the duel, sweating and panting, over the 64 squares.

Meanwhile the commentator shifts surreally from one activity to the other - "he's got him on the ropes with some jabs and a powerful right hook", and now "Re1, an ingenious move seizing control of the open file". There have been chess boxing contests in London and LA, Kolkata and Tokyo.

One of the most insightful of chess commentators, grandmaster Jonathan Rowson, says that boxing is the sport that most closely resembles chess. "In part it's the purity of the competition," he says. "There is virtually nothing to mediate the one-to-one combat. Boxing has gloves, but there are no balls, no goalposts, no clubs or racquets."

Then there's the brutality. In boxing this is transparent. In chess it's sublimated but no less real. "The emotional impulse behind chess, and the pain it inflicts, is comparable - but just takes a different form," says Rowson. In chess, defeated players have nothing to blame other than the inadequacy of their mental apparatus - cognitive shortcomings with which they have to live each and every day. As such, defeat can be psychologically crushing.

And victory in chess, especially but not exclusively at the elite level, requires an extraordinary will to power. The former American world champion Bobby Fischer once said that he enjoyed the moment when he could feel the ego of his opponent crumbling.

And the Russian world champion Garry Kasparov, just as blunt, described chess as "the most violent sport there is", avowedly aiming to "destroy the adversary's ego". It's perhaps no coincidence that both boxing and chess are overwhelmingly male activities, and that the ferocious language used to describe chess would be equally apt for boxing. Chess players talk of "crushing" and "smashing" and "destroying" their opponents.

Media playback is unsupported on your device Media caption The BBC's Christian Parkinson takes to the ring - and the board

Lennox Lewis plays chess almost daily. He credits the game with keeping him out of trouble during his tough upbringing in east London. "When someone calls you a name you want to punch them out… but chess teaches you to think through the next moves."

He also believes it helped him in the ring itself, even in key bouts such as his famous fight against Mike Tyson. Tyson, he insists, was merely a one-dimensional fighter, lacking a sophisticated strategic sense. As in chess, Lewis had a plan. Against Tyson, as on the chess board, Lewis aimed to control the centre.

The chess pieces seem rather fragile in the former boxer's huge hands, whose giant 6ft 5in frame was always an intimidating presence for opponents.

Asked about the central appeal of the game, the erstwhile undisputed heavy-weight champion of the world, resorts to the metaphor of conflict: "I love the mental war".

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