Tyson became youngest heavyweight champion on Nov 22, 1986
Former boxer Mike Tyson became the youngest ever heavyweight champion at the age of 20 after knocking out Trevor Berbick on November 22, 1986, in his WBC heavyweight title fight in Las Vegas, Nevada. Following the result of the bout, Tyson said, "I will also be the oldest heavyweight champion." Notably, Tyson only lost six bouts in his 58-bout-long career.