Boxing: Nathan Cleverly admits to putting title on line Nathan Cleverly admits he is facing the most important fight of his career on Saturday, and taking a gamble with his career. But though his opponent is the bookies' favourite to win, it is someone Cleverly chose himself. Sergey Kovalev has secured 19 of his 21 professional wins via knockout, with 18 of those coming within three rounds. But despite the Russian's formidable power, Cleverly will put his WBO light-heavyweight world title and 26-0 unbeaten record on the line in Cardiff in an attempt to break into what promoter Frank Warren describes as "some real big-money fights." Saturday's showdown is a considerable step up from Cleverly's last title defence in the Welsh capital - a convincing unanimous points decision victory over Tommy Karpency. But Warren and Cleverly believe it is a risk worth taking with a contract with American cable network HBO on offer should Cleverly win. "It is the most important fight of my career," Cleverly admitted, "potentially the best fight of my career as well. Potentially the best opponent I have faced, so this is a tremendous fight. We like to fight on the front foot and it is going to be explosive. Warren added: "It was Nathan who wanted this fight, he suggested it to me in a meeting we had a few months ago. Having been involved with Nathan from day one, this is a fight which can project him into some real big-money fights. Cleverly's father and trainer Vince has no doubt his son will emerge victorious at the Motorpoint Arena. "Whatever the Russian tank brings for Nathan, I think Nathan has the artillery to blow up that tank," he said. It won't be easy but I only see one winner. Nathan has trained like the challenger, not the champion and he definitely wants to win this fight to bring on Bernard Hopkins.