Gelsenkirchen - Ukraine's Vladimir Klitschko retained his world heavyweight titles by handing Uzbek fighter Ruslan Chagaev his first defeat thanks to a technical knockout after the ninth round on Saturday.
Klitschko, 33, held on to his IBF, IBO and WBO belts when the referee stopped the fight before the start of the 10th round in front of 61 000 fans with the WBA champion-in-recess bleeding from a large cut above his left eye.
"Tonight we, my team and I, beat a reigning world champion and you were here to witness it," Klitschko told the cheering crowd in the sold-out Schalke 04 soccer stadium.
"You cannot underestimate Chagaev. He's a terrific fighter. Today he did everything to beat me but I was better," he added.
Standing 1.99 metres tall, Klitschko initially held the challenger, who is 14 centimetres shorter, at bay with his longer reach before knocking his opponent down with a powerful left-right combination midway through the second round.
Unable to get close to the champion, Chagaev, who had a 25-0-1 record going into the fight, took a series of punishing jabs that slowly chipped away at his defences.
He suffered a three centimetre cut above his left eye in the sixth round but battled on gamely.
Chagaev, 30, who did not face WBA champion Nikolai Valuev after the Russian pulled out of their fight late last month because the Uzbek had the hepatitis B virus, managed to come back and landed a couple of body blows.
But Klitschko dominated in the eighth and ninth rounds, repeatedly forcing Chagaev to the ropes and landing dozens of punches as his shaken opponent's eye bled profusely.
Referee Eddie Cotton inspected the wound after the ninth round and decided to stop the fight in favour of the Ukrainian whose impressive performance takes him to 53-3-0.
Klitschko, whose brother Vitaly holds the WBC crown, was initially scheduled to fight David Haye before the Briton pulled out with an injury earlier this month.
Chagaev admitted he struggled against a better opponent.
"I searched for the keys to unlock a win but I just could not find any," he said.
"Today was just not my day. Today it was Vladimir's day."