Groves and DeGale hit London's O2

James DeGale will take on bitter rival George Groves on the same night Nathan Cleverly challenges for the WBO World Light-Heavyweight title against Juergen Braehmer. The mouth-watering double bill - which will rival the biggest nights in British boxing history - takes place on May 21 at The O2, London. Hall of Fame promoter Frank Warren confirmed the huge show, which will be screened by live and exclusive on Sky Box Office, at a press conference in London today. Tickets will go on sale on Friday, and it's certain to be the hottest ticket in town. Speaking at the press conference Warren hailed DeGale and Groves' British and Commonwealth super-middleweight title clash as a throw back to the showdowns between Nigel Benn, Chris Eubank and Michael Watson in the 1980s and 1990s. Warren has spent weeks negotiating for the fight to go ahead after purse bids last month. And he has agreed a deal that delivers a showdown every fight fan wants to see. DeGale and Groves fought as amateurs - the latter won - and DeGale went on to win gold at the Beijing Olympics. They have been bitter enemies ever since. Recently they have swapped insults, with DeGale insisting he will take revenge by knocking out his fellow west Londoner. British champion DeGale lifted the British title with a superb ninth-round stoppage of Paul Smith, while Groves - also unbeaten - holds the Commonwealth champion. Main on the show features Cleverly's eagerly anticipated world title clash with Braehmer finally getting the go ahead. The unbeaten Welshman is aiming to become one of the UK's youngest-ever world champions, and is already the interim WBO holder. Hard-hitting Braehmer comes to the UK as a world class talent and bona fide world champion. "This will be one of the best shows that I have ever put together," said Warren. "The super-middleweight division has always had a special place in the hearts of the British public. "I promoted some great champions in Joe Calzaghe, Chris Eubank, Steve Collins and Nigel Benn, but I believe DeGale can be better than all of them. "This fight against Groves will be an absolute war though, and it's a massive test. "Not only are the British and Commonwealth titles on the line, but pride is as well, and that makes this is a very special occasion. "Cleverly and Braehmer is one hell of a fight too. "Cleverly is one of our best prospects and this is his chance to make a massive statement. "And who knows, one day he might end up fighting James DeGale or George Groves up at light-heavy." Warren has previously promoted two blockbuster cards at the O2, when Enzo Maccarinelli and David Haye fought for three world cruiserweight titles. He also staged Amir Khan's Commonwealth lightweight title thriller with Willie Limond at London's biggest indoor venue.