Cassius Clay aka Muhammad Ali (the name adopted after converting to Islam) in my opinion is to be considered one of the greatest boxers of all time at least before the forced stop due to disqualification for failing to enlist to the Vietnam War having declared conscientious objector.
Trained by Angelo Dundee, Clay came to win the world heavyweight title just twenty-two years beating in seven innings Sonny Planks (Miami, February 25, 1964). He had a special technique in essence was never still revolved like a top around their opponents, through the saltellini similar to a dance, often with the low guard, then he struck and fell back making it impossible to answer all of their opponents and with harmony and class that was a sight to see him boxare Many say that the downward Cassius Clay began in 1978 when the young Larry Holmes defeated him by TKO in the 11th recovery. Already since his return to boxing after the stop Clay was not him.
In fact from the first defeat suffered by Joe Frazier in 1971, in the Clash of the Century at Madison Square Garden, the first meeting after the compulsory period of inactivity racing Clay boxava as before too static on the legs to be him. Ali after losing to Joe Frazier wanted to return the ring to show the world that he was still the number one and we managed to get back world champion AMB only in 1974 putting the mat George Foreman in Kinshasa, in a meeting known to history and today reminded the manuals as one of the biggest sporting events ever.
Foreman was given by bookmakers as favorite, and his victory was given up to three times more likely than a defeat. The shares were affected by the last defeat of Ali with Frazier, and by the fact that Foreman had won the world title by beating their Frazier. We see a summary of what was surely the most famous media spectacle 70s.