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
NWA World Heavyweight Championship and Total Nonstop Action Wrestling (TNA, now Impact Wrestling). With many territorial promotions appearing across the United States, the NWA was formed in 1948 as an overall governing wrestling body. Like franchises, these territories had the option of NWA membership. The promotion owners had to recognize the NWA Heavyweight, Junior Heavyweight, and Light Heavyweight Champions as world champions while retaining their own ownership and top champion. Ric Flair holds the record for the most reigns with nine. The current champion is Nick Aldis, who is in his second reign. Every year, the NWA World Heavyweight Champion would travel to each