Muhammad Ali, born Cassius Clay, is widely regarded as the The Greatest Boxer of all time. Born in 1942, a young Ali entered professional boxing at just 18 years of age and soon went on to become the undisputed World Heavyweight Champion. He fought in a total of a 61 professional bouts, winning a whopping 56 of those, with 37 being knockouts.

In a career spanning over 2 decades, Muhammad Ali lost just 5 matches -

1) vs Joe Frazier (1971)

2) vs Ken Norton (1973)

3) vs Leon Spinks (1978)

4) vs Larry Holmes (1980)

5) vs Trevor Berbick (1981)

An interesting fact about his losses is that he defeated them all in their re-matches, except Larry Holmes.

What makes Muhammad Ali even greater is the fact that towards the end of his career, he was plagued by the onset of Parkinson's. Declared unfit for the fights, Ali still went ahead and fought with all valour. He died in 2016 after a prolonged stint with Parkinson's.

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