Canada's George Chuvalo is widely considered to have the best chin in boxing history. He was never knocked down in 93 professional heavyweight fights, even against the likes of Muhammad Ali and George Foreman. In the build up to his second fight with Ali, 'The Greatest' predicted he would be the one to finally drop Chuvalo, saying: "I'm not gonna let it be said there was ever a heavyweight that didn't fall. They have pictures showing my heels. Jack Johnson fell, Jack Dempsey fell, Sugar Ray Robi