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
WCW International World Heavyweight Championship was the first and last titleholder. The WCW International World Heavyweight Championship has its origins in the NWA World Heavyweight Championship, the principal championship of the National Wrestling Alliance (NWA). The NWA was a syndicate of wrestling promotions who would book an overall champion. In 1991, the NWA World Heavyweight Champion was Ric Flair, who held the title when he wrestled for WCW. Flair was simultaneously considered the WCW World Heavyweight Champion; he was stripped of both titles because he left to work for rival company World Wrestling Federation (WWF, now WWE). Lex Luger won the vacant WCW World Heavyweight