The distance (boxing) 19, 1987. While the International Boxing Federation, which had recently broken away from the WBA, continued to hold onto the position there was no documented medical evidence to show a 15-round fight is more dangerous than a 12-round fight, they eventually voted to shorten their championship distance to 12 rounds as well on June 3, 1988. The last heavyweight 15-rounder title fight was on October 16, 1987 between Mike Tyson and Tyrell Biggs. The last middleweight 15-rounder title fight was a World Boxing Board title match on June 7, 1997 in which Jose Alfredo Flores won a split decision over
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