Claim: Wladimir Klitschko is a fighter.

Professional boxing , or prizefighting , emerged in the early twentieth century as boxing gradually attained legitimacy and became a regulated , sanctioned sport . Professional boxing bouts are fought for a purse which is divided between the boxers as determined by contract . Most professional bouts are supervised by a regulatory authority to guarantee the fighters ' safety . Most high-profile bouts obtain the endorsement of a sanctioning body , which awards championship belts , establishes rules , and assigns its own judges and referee .   In contrast with amateur boxing , professional bouts are typically much longer and can last up to twelve rounds , though less significant fights can be as short as four rounds . Protective headgear is not permitted , and boxers are generally allowed to take substantial punishment before a fight is halted . Professional boxing has enjoyed a much higher profile than amateur boxing throughout the 20th century and beyond .   In Cuba professional boxing is banned -LRB- as of 2007 -RRB- . So was also the case in Sweden between 1970 and 2007 , and Norway between 1981 and 2014 .