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 Championship (WWE) December 15, 2013, to unify the titles. Subsequently, the WWE Championship was renamed WWE World Heavyweight Championship. The unified championship retained the lineage of the WWE Championship, and the World Heavyweight Championship was retired. With his victory over John Cena, Randy Orton became the final World Heavyweight Champion. Like with the Undisputed Championship, the Big Gold Belt was used in tandem with the WWE Championship belt to represent the WWE World Heavyweight Championship until a single belt was presented to then champion Brock Lesnar in August 2014. The following is a list of dates indicating the transitions of the World