GELSENKIRCHEN, Germany — Wladimir Klitschko again proved his dominance of the heavyweight division, stopping Ruslan Chagaev in a hastily put together title fight Saturday night before 61,000 fans at a German soccer stadium.

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.

Referee Eddie Cotton stopped the fight before the 10th round.

"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.

He 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.