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 Historic Light Heavyweight Championship become the third ever NWA World Historic Light Heavyweight Champion. Bucanero became the first champion to have not also held the previous NWA World Light Heavyweight Championship. Due to the championship being vacated on February 23, 2015, CMLL held a tournament for the vacant light heavyweight championship starting March 1, 2015. La Sombra and Rey Bucanero outlasted Atlantis, Blue Panther, Dragón Rojo Jr., Ephesto, Misterioso Jr., Mr. Águila, Niebla Roja, Stuka Jr., Valiente and Último Guerrero in a 12-man "torneo cibernetico" elimination match. On March 8, Bucanero defeated La Sombra to win the tournament and the vacant championship. NWA World