Undisputed champion recognised a different champion. The disputes were usually short-lived as a lucrative fight would be organised between the rival champions. The longest split was ten years, of the middleweight title, between Mickey Walker's move up to heavyweight in 1931 and NBA champion Tony Zale's defeat of NYSAC contender Georgie Abrams in 1941. An early use of "undisputed" appears in a "New York Times" preview of the 1941 fight. The growing popularity of boxing outside of the USA led to creation of various boxing organizations, each strengthening their influence (most notably BBBofC) and having their own champion. This resulted in a
World Series of Boxing and Bantamweight (50–54 kg). In the fourth season (2013–14), the number of weight classes was increased to ten, and they are same as in amateur (Olympic) boxing. Teams played in the WSB: All WSB Live shows are distributed worldwide by Fighting Spirit. World Series of Boxing The World Series of Boxing or WSB is an international boxing tournament that allows amateur boxers to compete professionally while maintaining amateur status and Olympic eligibility. It is organised by AIBA. Unlike amateur boxing, competitors taking part in sanctioned World Series of Boxing bouts must be bare-chested and are not permitted to wear protective