SUGAR RAY LEONARD believes David Haye's speed could prove to be Vitali Klitschko's downfall. Londoner Haye continues to chase a showdown with the WBC heavyweight champion — despite hanging up his gloves last year. Father Time appeared to be catching up with Klitschko as he successfully defended his title against Dereck Chisora last month. And Sugar Ray has highlighted Haye's movement as his main asset should he secure a crack at the 40-year-old Ukrainian. The boxing legend told SunSport: "David's not that big of a heavyweight, so size will be a factor. "If that fight comes to fruition, David will have to be mobile. He can't be a stationary target." Haye, 31, was widely criticised for his performance against Klitschko's younger brother Wladimir. The Hayemaker dropped his WBA title in Germany before blaming a broken little toe for his below-par display. He is willing to come out of retirement for a crack at Vitali — which comes as no surprise to Leonard considering the potential rewards on offer. The American said: "The money a fight like that would generate certainly doesn't hurt. "It creates a little incentive and that extra bit of motivation." While the Klitschko brothers may not be everyone's cup of tea, Leonard is impressed with the way they have dominated the heavyweight division. He added: "From my understanding, they're huge over here in the UK. "In America, although they're known by boxing fans, they're not household names with the wider public. "But you have to give them credit, they use what they have. I've been impressed with them for a long time." Sugar Ray Leonard's autobiography, The Big Fight, is available now in all good book shops.