when did they change boxing to 12 rounds
The distance (boxing) The following year on March 27, 1983, the first ever heavyweight title fight scheduled for 12 rounds under that rule was held by the WBC between Larry Holmes and Lucien Rodriguez.[9] The World Boxing Association, from which the World Boxing Organization had not yet separated, later followed suit[10] by voting to reduce their championship distances to 12 rounds on October 19, 1987.[11] 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.[12]
Mike Tyson vs. Michael Spinks Tyson attacked Spinks from the opening bell, landing a solid left hook in the first ten seconds and forcing Spinks to cover up. Spinks clinched and was driven back to the ropes by another Tyson attack. He moved off the ropes but Tyson trapped him again; a left uppercut and a right hand to the body forced Spinks to take a knee after a minute, which marked the second time Spinks had been knocked down in his professional career since Braxton during the eighth round of their 1983 encounter.[37] Spinks took a count of four before rising. As the two men moved towards each other Tyson turned away from a Spinks right hand and responded with a left-right combination to the head which put Spinks down again. This time he was unable to rise and referee Frank Cappuccino counted him out. The fight was over after 91 seconds,[5] presently the sixth shortest heavyweight title fight in history.[38] Just ten punches were landed, eight by Tyson, two by Spinks.[39] The round was named round of the year for 1988 by Ring Magazine.