Cornelius Johannes Sanders was a South African professional boxer who competed from 1989 to 2008. He won the WBO heavyweight title in 2003 after knocking out Wladimir Klitschko in two rounds, which was considered one of the biggest upsets in heavyweight boxing history; The Ring magazine named it the Upset of the Year. In 2004, having vacated the WBO title, Sanders faced Wladimir's brother Vitali Klitschko in an unsuccessful challenge for the vacant WBC and Ring heavyweight titles. He also held the WBU heavyweight title from 1997 until 2000 and the South Africa national heavyweight title in 1991. World heavyweight champion (WBO) from March 8, 2003 to October 9, 2003. Wiki link