Wladimir Klitschko Universum Box-Promotion in Hamburg under the tutelage of Fritz Sdunek, often being featured on fight cards alongside his elder brother Vitali. After building an undefeated record of 24–0 with 22 KOs, he suffered his first loss to 24–13–1 Ross Puritty, in what was Klitschko's first and only professional fight in Ukraine. Puritty forced Klitschko, who had at that time not gone beyond 8 rounds, to punch himself out. Klitschko began to be overwhelmed in the 10th round and went down twice but was allowed to continue. At the start of the 11th round, with Puritty continuing to land hard punches,
Wladimir Klitschko vs. Ruslan Chagaev had beaten Vitali Klitschko in June 2003. Klitschko dominated the fight, with him winning every round on one scorecard, and all but one on the other two. He knocked Chagaev down in the second round and opened a cut over his left eye in the eighth. The fight was stopped after the ninth round. Inmediatly after this bout Chagaev would lose his "Champion In recess" status and would not fight for eleven months. Klitschko would make two defences against Eddie Chambers and a rematch with former WBC champion Samuel Peter, before a unification bout with now WBA beltholder Haye in