Frank Warren to sue Ricky Burns after Scot ends 'nightmare' to joins rival promoters Matchroom Burns, the 29-year-old Scot, has followed super-middleweight George Groves in joining Hearn's growing stable of fighters, which includes world supermiddleweight champion Carl Froch, and world light-heavyweight prospect Tony Bellew. Hearn, 33, outlined the move on Monday in central London, with Burns flanked by his trainer Billy Nelson, who said he had gone back to his shift job as a residential care worker in the last few weeks. "We've been provided with a letter from Ricky Burns as confirmation that he has terminated his agreement," explained Hearn. One thing we would never do is discuss contractual issues or make an offer to a fighter who is under contract. Once we received that letter of termination, it is not up to us to determine whether those breaches are correct or incorrect. That is between the previous promoter and the fighter. We have advice from our lawyers and I'm very comfortable. There is no contract now. Ricky has terminated that agreement. If Frank [Warren] believes Ricky has terminated that contract wrongly, no doubt they'll meet each other in a court of law. Warren's maintained claim, nonetheless, is that Burns is contractually committed to his postponed unification contest Vázquez. The fight against Vázquez was originally to take place at Wembley Arena on Saturday night, but was delayed after the Mexican revealed he was suffering with a stomach ailment. Burns has not fought since he retained his WBO title with a fourth-round stoppage of Kevin Mitchell last September. He explained yesterday: "For the last year or so there have been a few issues that needed to be sorted out that never happened, obviously there were that many things one after the other. Me and Alex [Morrison, his manager] sat down and we decided we had to do something. The whole six months [since the Kevin Mitchell fight in September] have been a nightmare for me. Hearn outlined that two dates - May 11, and then September - were already planned for Burns to compete. Both events will be in Glasgow, with the opponent for May yet to be named. He did not rule out Vázquez as the opponent, nor that Burns would give up the WBO 135lb belt.