It's hard to imagine too many similarities between the cerebral game of chess and the bone-juddering discipline of boxing and yet there is a new sport that melds the two.
When you think of chess players, you probably think of tangle-haired geniuses, reclusive Russians, and the boys at school who were too delicate to play in the yard.
Jab: Straight arm punch, using reach to keep distance
Hook: Semi-circular punch to the side of the head
Uppercut: Powerful rising blow
Sicilian Defence: Opening that is black's best chance of winning
King's Gambit: Old-fashioned but violent and entertaining opening for white
Giuoco Piano: Oldest known opening and the one most players learn first
You probably don't think of bulging biceps, iron jaws and sweat flying. That's why the mere mention of chessboxing causes so many raised eyebrows.
It's a mixture of chess and boxing - one round of chess is followed by a round of boxing and so on until the winner is declared by knockout, checkmate or points victory.
The sport, brought into reality in 2003 by a Dutch performance artist inspired by a French comic, came to the UK in April and has its headquarters at a boxing gym in north London. On the continent, the sport's epicentres are in Amsterdam and Berlin.
Some might assume that boxers lack the cerebral skills required for the game of kings, while a single punch would knock a chess player's glasses clean off his head?
But tactical thinking, stamina and quickfire responses are vital for both sports. The two best heavyweights of recent years are both keen chess players. Lennox Lewis played chess in breaks in training and is a supporter of chess tuition for children. Vitali Klitschko once said: "Chess is similar to boxing. You need to develop a strategy, and you need to think two or three steps ahead about what your opponent is doing. You have to be smart."
It's hard to concentrate after you've been punched in the head
But for most non-boxing, non-chess fans, the links are esoteric.
"It's a devilish combination," the sport's Dutch inventor Iepe Rubingh tells a crowd of shaven-headed East End geezers and wild-haired cool kids at Bethnal Green Working Men's Club, east London.
He has come to see the latest instalment in chessboxing's rise in popularity - a UK international bout.
A large chessboard sits in the middle of a boxing ring beneath the club's dusty glitter ball.
As paramedics wait behind the ring and a rockabilly DJ plays 80s electro music to the sold-out venue, there is a palpable sense of uncertainty and menace.
Glass jaw: Someone unable to withstand punches
Spoiler: A boxer who avoids defeat by tactics like repeated holding
Book: Moves that conform directly to books on opening theory
Blunder: Inadvertent loss of piece or pawn
Sac: Short for sacrifice
It lifts when the first fighters take to the stage, with a compere whipping the crowd into a frenzy and a traditional glamorous lady circling the ring with a sign declaring "Round One". The boxers then sit down and play chess. A bout of chessboxing stretches to 11 rounds - six of chess (four minutes each) and five of boxing (three minutes each).
Event promoter Tim Woolgar has put his money where his mouth is by taking part in the first bout. Unfortunately he is up against Konrad Rikardson from Sweden, a confident chess player and even more confident boxer.
As their chess moves are tracked on a giant computer screen, a commentator guides us through the game and evaluates the players' tactics.
A blokey cheer erupts whenever a piece is taken, but the boxers wear headphones to block out the noise. We are told they pump out Eric Clapton songs all night to increase the players' aggression.
"Go on - 'ave him!" shouts someone in the audience after a particularly good move. "Bash his bishop!", another yells, while the commentator sagely notes: "It's a pawn storm."
Wolfram von Stauffenberg and Andy Costello are chessboxing heavyweights
Minutes later the mood darkens as the board is moved aside, gloves and gum shields are put on and the boxing begins.
As the pair bob around the ring ducking and weaving, jabbing and defending, it becomes clear that they are deadly serious about their sport.
Woolgar takes one head blow after another yet minutes later returns to drip sweat over the chessboard.
He defends himself admirably but suffers a further physical pounding before Rikardson snatches his queen. The crowd goes wild.
Two further fights take place including a match between Bob "The Red Kite" Innes and James "Jimbo Slice" Taylor, who prove to be fierce in the ring but not so confident at the chessboard. The Red Kite soon falls to the floor.
By 2020 we want chessboxing to be up there with the other professional sports
Tim Woolgar, London Chessboxing Club
The headline fight is an impressive grudge match between Germany's Wolfram von Stauffenberg (white pieces) and Andy Costello from Exeter (black pieces).
It is clear why they are hailed as chessboxing champions as their rapid, shrewd chess playing is matched only by the vicious ferocity of their boxing.
As the pair tussle in the ring, half the crowd is baying for blood while the remainder winces as blows connect. In a surprising twist, the audience is unanimous in its enthusiasm for their chess playing.
As Costello took the checkmate it seemed Von Stauffenberg had a narrow escape.
After the tournament, Woolgar has recovered enough to explain the pain and pleasure of chessboxing. "I took an almighty pounding. I have a sense that it didn't do me any good."
Chess Boxing has already proved popular in Germany
Nevertheless he is undaunted in his enthusiasm for the hybrid sport, adamant that chessboxing has an "instant appeal" that wins over "a cross section of the community".
He now wants to encourage more young people to take it up and is aiming for it to be recognised as an Olympic sport.
"We're being realistic about it, so we're not going for 2012 or even 2016," he said. "But by 2020 we want chessboxing to be up there with the other professional sports."
If its popularity continues to grow, chessboxing might just make it.
Below is a selection of your comments.
Anyone who has ever been in the ring will testify to the increased speed of mental processing bought on. These two sports are coupled nicely - finally a pastime that you can encourage your kids to do to improve their IQ and their physical capability. Patrick, Cambridge, UK
I play league chess and while this mash-up seems a bit contrived, it would certainly make sure no seven-year-old whizz-kid ever beats me ever again. Jer, Bristol
This is complete and utter rubbish; "By 2020 we want chessboxing to be up there with the other professional sports". It's two sports fused into, well you can't even say one because they aren't. They are still two separate sports played sequentially; chess - boxing. To me this would interrupt the pace and tension of the former and latter. Aaron Smiles, Newcastle
I understand Lennox Lewis plays a mean game of chess. But I don't think he's ever tried this. Mark Shanahan, Sussex
In this society where specialism is paramount, it is great to see a sport where a wide range of skills is needed. I might just give it a go. Dan, Brighton
I have never boxed, but I do wrestle and play chess (albeit not at the same time), and have found the sport and the game to have remarkable similarities: you are always thinking one or two moves ahead; it is possible to arrive at a stalemate; and the tables can turn quickly and irrevocably if one of the two opponents makes a mistake. All this just goes to show that you don't have to be a meathead to take part in combat sports. Hugh, Brussels, Belgium
Yep, no coverage of the chess world championship but we do get this. I am all for coverage of new sports but can't you also cover the classics? This year's chess championship was the best for many years. Simon Hayward
Given that the BBC couldn't be bothered to cover the recent world chess championship until after it had finished, why is it considered appropriate to cover this rubbish instead? Justin Horton, Huesca province, Spain
I'm now looking forward to Boxing Bingo or Shot-put Scrabble. How 'bout Battleships with real battleships? Steve, Kew
Steve, I believe that exists and is known as "war". David Evans, Frome, United Kingdom
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