Boxing in the 1970s was world champion when Ali returned. Former world champions Jimmy Ellis and Floyd Patterson as well as George Foreman, Oscar Bonavena, Jerry Quarry, Earnie Shavers, Leon Spinks, Ken Norton, as well as Larry Holmes, Ron Stander, Chuck Wepner, Jose King Roman, Light Heavyweight champ Foster, John Tate, Jimmy Young, Ron Lyle, Joe Bugner, Scott LeDoux and many others added intrigue to the division. Don King surged as a leading boxing promoter, and champions Duran, Monzon and Ali had historic rivalries with Esteban De Jesús, Rodrigo Valdez and Frazier, respectively. Boxing in the 1970s During the 1970s, boxing was characterized by
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