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,
Lennox Lewis vs. Vitali Klitschko against Kirk Johnson in which only Lewis' IBO title would be on the line. Klitschko was to fight on the undercard and take on Lewis in December. Before the Lewis–Johnson fight could take place, Johnson was forced to pull out with a chest injury. As such, Lewis and Klitschko agreed to face one another on June 21, rather than later in the year as originally planned. Though Klitschko came into the fight as the underdog, he was able to get off to a great start in the fight. Klitschko was the aggressor through the first two rounds and landed many