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Sugar Ray Leonard
Sport: Boxing
Career; Former Welterweight and Middleweight Boxing Champion; 1981 Sports Illustrated's Sportsman of the Year
Age at Unretirement: 27
After suffering an eye injury, Leonard retired in November 1982. He returned to fight in May 1984, defeating middleweight champion Marvin Haggler in May 1986. He retired after this fight and would attempt multiple comebacks later on, but to no avail.
