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 Boxing Organization (as they did with several established champions in the lower weight divisions), the WBO sanctioned a fight between two relatively unknown fighters, Francesco Damiani (winner of the super heavyweight silver medal at the 1984 Summer Olympics) and Johnny DuPlooy, to determine the inaugural holder of its own heavyweight title in 1989. All other sanctioning bodies of boxing recognized the then-undefeated Mike Tyson as the undisputed heavyweight champion. Damiani, meanwhile, went on to become the first WBO heavyweight champion. At heavyweight, especially in the United States, the organization initially struggled to gain credibility as a major sanctioning body, with WBO heavyweight