5. Lennox Lewis
He won world championship in 1992. But before that, he clinched an Olympic Gold at 1988 games. During his career, he defeated major names such as Evander Holyfield, Frank Bruno and Mike Tyson. Lennnox Lewis is the last undisputed heavyweight world champion. Throughout his career, he fought 44 fights and won 41, losing 2 and drawing 1.
