With 21 successful title defences, Ottke was the fourth European boxer to retire as an undefeated world champion, after Jack McAuliffe, Terry Marsh, and Michael Loewe; Joe Calzaghe later became the fifth.

Ottke held amateur wins over Antonio Tarver, Chris Byrd, Michael Moorer, Zsolt Erdei and Juan Carlos Gómez.

Ottke failed to pass the quarterfinals of the few World Championships and Olympic games he participated in, apart from the Moscow 1989, where he dropped out of the semifinals.

Less than a year later on 24 October 1998, he won the IBF super middleweight championship from Charles Brewer via a disputed decision victory.

After this he made 16 successful defenses of his IBF title against fighters such as Thomas Tate (twice), Glen Johnson, Silvio Branco, James Butler, Anthony Mundine, Charles Brewer in a rematch, and a controversial points win against Robin Reid.