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,
Vitali Klitschko and awarding Byrd the win by RTD. At the time of the stoppage, Klitschko had won 8 of 9 rounds on one judge's scorecard, and 7 of 9 on the two others. Klitschko, who was later diagnosed with a torn rotator cuff, received much criticism for quitting the fight. Klitschko rebounded from his loss to Byrd by reeling off five victories in a row, earning himself a shot at WBC Heavyweight Champion Lennox Lewis. The fight between Lewis and Klitschko was to take place in December 2003, and Klitschko signed for a tune-up fight on 21 June 2003 as part