Undisputed champion he was still described as "undisputed champion" by some reports. After Joe Calzaghe's super middleweight victory over Mikkel Kessler in November 2007, he was frequently described as "undisputed champion". Others disputed this, because although he held the WBA, WBC, and WBO belts, he vacated his IBF title in November 2006 rather than face a mandatory challenger, and immediately vacated other titles as well. The unified champion is defined as a boxer that holds at least two world championships of major sanctioning bodies (WBA, WBC, WBO or IBF) in their respective division. Around 2004, the World Boxing Association recognized three different
World Boxing Super Series commemorative Diamond title. Additionally, the winners will receive the Muhammad Ali Trophy. Due to the 'bracket style' nature of the tournament, the winner of each tournament will claim all world titles in the field. Oleksandr Usyk, the winner of the cruiserweight tournament, unified the WBO, IBF, WBC and WBA cruiserweight titles and became the first cruiserweight undisputed champion in over a decade, and the first in the four-belt era. Current broadcasters Source: World Boxing Super Series The World Boxing Super Series (WBSS) is a professional boxing tournament organised by Comosa AG. Each weight class features eight boxers competing in an