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
Weight class (boxing) reasons, fighters cannot fight at a higher weight. This also meant that even the heaviest weight class has a limit, albeit a lower bound. The lower limit for "heavyweight" was established in 1948 at 81 kg. When a new limit of 91+ kg was established in 1984, the name "heavyweight" was kept by the 81+ kg class, and the 91+ kg class was named "super heavyweight", a name not currently used in professional boxing. Classes are as follows: At the Olympics, each weight-class is a separate single-elimination tournament. The competition begins with the first round of the lightest weight class