Based on;
Accomplishments and Skills;
Muhammad Ali
Evander Holyfield
George Foreman
Larry Holmes
Lennox Lewis
Mike Tyson
Joe Frazier
Riddick Bowe
Kenny Norton
Jimmy Young
Based on Superstar Status or Drawing ability;
Muhammad Ali
Mike Tyson
Evander Holyfield
George Foreman
Joe Frazier
Larry Holmes
Riddick Bowe
Lennox Lewis
Gerry Cooney
Ken Norton