There are flashes of the legendary Muhammad Ali wit and quick-thinking delivery peppered throughout this otherwise rather long and ponderous story of the life of Cassius Clay from relative poverty through to his mastery of not just the boxing ring but of the television media that, at that point, fed successfully from this truly global sport. It's Will Smith who takes centre stage after his gold medal victory at the Tokyo Olympiad in 1964 and like many other pugilists in history, his character offers the down-trodden, working class, an inspiration. With sweat, tears and hard work he can…