The IBF and WBO champion added the Ring Magazine belt to his haul, knocking Chagaev down in the second round and opening a cut over the Uzbekistan-born fighter's left eye in the eighth.

The official time was 3:00 of the 9th Round for the IBF, WBO, IBO and Ring Magazine Heavyweight Championship.

"You can't underestimate Chagaev," said Klitschko, who stands with his brother Vitali as clearly the best in the division. "He did everything today, but I was better."

Chagaev, who is the WBA's "champion in recess," raised a deep bruise under Klitschko's right eye, but was done in by the Ukrainian's height advantage and superior power. With his strong left jab and hard straight rights, Klitschko (53-3, 47 KOs) bloodied Chagaev and never appeared in danger.

The sellout crowd was the biggest boxing audience in Germany since Max Schmeling knocked out Adolf Heuser in front of 70,000 people in Stuttgart in 1939.

"Throughout the fight, I searched for the keys to unlock a win, but I just couldn't find them," said Chagaev, whose win over Carl Davis Drummond in February was stopped by a similar cut above his left eye.

The matchup at the Schalke soccer club's Veltins Arena was originally billed as a showdown between Klitschko and former cruiserweight champ David Haye, and the two had gone on a worldwide press tour in which the outspoken Haye flaunted T-shirts showing him standing in the ring with the decapitated heads of the Klitschko brothers.

But the British fighter, whose only victory since moving to heavyweight was a knockout of Monte Barrett in November, pulled out earlier this month citing a back injury. He asked to reschedule the fight for July, but Klitschko wanted to keep the date and sellout crowd.

"I never, ever worked with such unprofessional people as David Haye and his team," Klitschko said, adding that he would consider arranging another fight against him. "I think he's going to end up on the floor."

Klitschko found a replacement in Chagaev (25-1-1), who was supposed to fight Nikolai Valuev for the WBA title last month in Helsinki. That bout was called off after the weigh-in when doctors found Hepatitis-B antigens in Chagaev's blood.

Because the rules are different in Germany, Chagaev managed to pass a medical exam and was allowed to fight Klitschko, even though several organizations protested, including the American Association of Professional Ringside Physicians.

Valuev turned down an offer to fight Klitschko in Haye's place.

Klitschko said after the fight that he felt he was in better form than at any point in his career. He hasn't lost in more than five years, and at this juncture, it's becoming hard to believe there's anyone out there who can stop him.

"I'm not looking forward to proving my chin, because it's made of glass and I want to take care of it," Klitschko said, joking about those who once criticized him for not being able to take a punch. "So, I want to dominate my fights like I do pretty much all my best fights."