Updated

Vitali Klitschko stopped Polish challenger Tomasz Adamek in the 10th round to retain the WBC heavyweight title Saturday night.

Italian referee Massimo Barrovecchio stepped in 2 minutes, 20 seconds into the round, ending an utterly dominant performance by the Ukrainian.

The 40-year-old Klitschko was six inches taller than his opponent and used his size advantage, with the 34-year-old Adamek staggering back in the second, sixth and ninth rounds.

Klitschko improved to 43-2 with his 40th knockout. Adamek dropped to 44-2.

Klitschko and younger brother Wladimir retained their hold on all three major heavyweight titles.

"I think the referee made the right decision. He probably could have stopped it a minute earlier," said Wladimir, who holds the IBF and "super" WBA titles as well as the minor WBO and IBO belts.

Wladimir revealed the next Klitschko fight will be in December.

Adamek was cheered on by the majority of the 42,000 fans at the sold-out municipal stadium.

"He's a very good boxer," Klitschko said. "He was a cruiserweight champion, he was a light heavyweight champion, but he's not good enough to be a heavyweight champion because it's a whole other league."

Adamek tried to force the issue in the second round but was caught by a huge right hook that left him wobbling against the ropes and the crowd fearing an early outcome.

Adamek recovered slightly in the fourth, despite a bloody nose and mouth, but failed to really trouble Klitschko, who was in control throughout.

Barrovecchio checked Adamek after taking a powerful left-right combination in the sixth, and Klitschko's left foot gave way while pushing Adamek into the corner in the eighth.

"I twisted my foot and lost my balance," he explained.

Despite the delight it brought the crowd, the outcome was never in doubt, and Klitschko again had Adamek staggering after delivering a straight left jab to the head in the ninth.

It was only a matter of time before Adamek's challenge was brought to a halt.

"He was simply the better fighter and he won. That's sport. You win some and you lose some. This time I lost," Adamek said.

Klitschko's win set up a possible bout with David Haye, who was beaten by Wladimir for the WBA belt in July.

Haye planned on retiring before his 31st birthday in October, but the 30-year-old Londoner has indicated he'd welcome a fight against the older Klitschko.

Klitschko's trainer Fritz Sdunek said Thursday that the 40-year-old would only fight two or three bouts more, and that Haye would be a preferred opponent.