Who was the only boxer to fight Muhammad Ali, Joe Frazier and George Foreman? asked Bill Daley
This was the durable Canadian heavyweight George Chuvalo, who was never knocked down throughout a professional career that stretched to 93 fights, 73 of which he won.
Chuvalo, who was born in Toronto in 1937, lost on points to Ali in 1966 and 1972, while his defeats to Frazier in 1967 and Foreman in 1970 were the only times he failed to last the distance.
Chuvalo also fought three other sometime world champions - Floyd Patterson (in The Ring magazine's fight of the year in 1965), Ernie Terrell and Jimmy Ellis.
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