Mike Tyson is an athlete.
Mike Tyson . He reigned as the undisputed world heavyweight champion and holds the record as the youngest boxer to win a heavyweight title at 20 years , 4 months and 22 days old . This made Tyson the first heavyweight boxer to simultaneously hold the WBA , WBC and IBF titles , and the only heavyweight to successively unify them . Tyson retired from professional boxing in 2006 , after being knocked out in consecutive matches against Danny Williams and Kevin McBride . He was ranked No. 16 on The Rings list of 100 greatest punchers of all time , and No. 1 in the ESPN.com list of `` The Hardest Hitters in Heavyweight History . '' Sky Sports rated him as `` the scariest boxer ever , '' and described him as `` perhaps the most ferocious fighter to step into a professional ring . ''