Wladimir Klitschko was proclaimed the first unified heavyweight champion since Lennox Lewis as he outpointed Sultan Ibragimov in New York.
Klitschko put Ibragimov on the canvas but it was not a knockdown
The IBF heavyweight champion took his 50th professional win (50-3, 44 KOs) by unanimous decision (119-110, 117-111, 118-110) at Madison Square Garden.
WBO champion Ibragimov suffered his first defeat in 24 pro fights.
It was the first unification bout in the division since 1999 when Lewis beat Evander Holyfield in the same arena.
But Klitschko still needs Oleg Maskaev's WBC and Ruslan Chagaev's WBA versions of the title before he can fully unify the division.
I thought I was going to knock this guy out - it wasn't easy
Klitschko, 31, jabbed his way to a clear if unspectacular victory.
But his solid defense against the Russian southpaw failed to wow the crowd of 14,011 at Madison Square Garden.
Sporadic jeers punctuated the early rounds as Klitschko relied on his height advantage and his jab and seemed reluctant to unleash his powerful right hand.
Klitschko did land a big right to Ibragimov's head, and Ibragimov responded with a left to Klitschko's ribs as the action heated up a bit in the seventh.
And Klitschko hurt Ibragimov again with a right in the eighth, following up with another as Ibragimov went down, but it was ruled due to a push and not a knockdown.
Afterwards the victorious Ukrainian said he didn't want to risk throwing his right more and missing.
"I had to make sure I would land them," said Klitschko. "If I would miss I would lose the balance and it's hard to get back.
"I thought I was going to knock this guy out - it wasn't easy. I know you're not satisfied, but I have to keep the belts and knock everybody else out."
It was his fourth defense of the IBF title he won from Chris Byrd in April 2006.