Heavyweight unification series Heavyweight unification series The heavyweight unification series, also known as the Heavyweight World Series, was a sequence of professional boxing matches held in 1986 and 1987 to crown an undisputed champion of the heavyweight class. The series was produced by HBO Sports and promoted by Don King. It ended with Mike Tyson as undisputed champion, holding the championship belts of the International Boxing Federation, World Boxing Association, and World Boxing Council. Prior to the series, the last undisputed heavyweight champion had been Leon Spinks, who won the championship in his 1978 victory over Muhammad Ali. Spinks had been stripped of
World Heavyweight Wrestling Championship (original version) the sixth longest reigning world heavyweight champion in history behind Bruno Sammartino, Jim Londos, Lou Thesz, Verne Gagne (who all held their world titles for over seven years) and Bob Backlund (who held his for nearly six years). Joe Stecher defeated American Heavyweight Champion Charlie Cutler to become the first widely recognized world heavyweight champion after the retirement of Frank Gotch. On April 15, 1925, Stanislaus Zbyszko defeated previous champion Wayne Munn to win the championship. However, Munn continued to be recognized as the World Heavyweight Champion in Michigan and in Illinois. Ed Lewis defeated Wayne Munn on February 2,