Teofimo Lopez scored a convincing victory over Vasiliy Lomachenko in Las Vegas to become the undisputed world lightweight champion.

The New Yorker defended his own 135-pound IBF lightweight title and took Ukrainian Lomachenko's WBC, WBO and WBA belts, inflicting a first defeat in six years on his vaunted opponent - who stood at second in The Ring's pound-for-pound ratings going into the fight.

"I am ready to take over the world," said Lopez, who won by unanimous decision, with scores of 119-109, 117-111 and 116-112.

At just 23 Lopez, 16-0 with 12 knockouts, is the youngest fighter to become an undisputed four-belt world champion following an engaging battle at the MGM Grand Hotel and Casino that was closer than the judges' card suggested.

Lomachenko, now 14-2 with 10 knockout, had scored a unanimous decision win over England's Luke Campbell last August in London in his last outing.

"I think I won the fight," said Lomachenko. "But I am not going to argue it now.

"In the first half of the fight he won more rounds. In the second half I took it over. I don't agree with the scorecards. "