Russia's Denis Lebedev stopped Argentina's Victor Emilio Ramirez in the second round to unify the WBA and IBF cruiserweight titles on Saturday.

Lebedev, who came in as the WBA champion, moved well from the start and hit Ramirez with hard left uppercuts early in the second round, eventually knocking down the Argentine.

Ramirez beat the count and continued, but within seconds he was overwhelmed by more hammer blows from Lebedev's left, and the referee stepped in to stop the fight.

"It's excellent," Lebedev said in televised comments. "I knew what he was capable of and the tactics that my trainers had carefully worked out came good."

Lebedev improved to a 29-2 record, while Ramirez dropped to 22-3 with one draw.

The Argentine was given the IBF title by default last year when previous champion Yoan Pablo Hernandez was stripped of the belt for inactivity, and his only other fight as champion was a split-decision draw against Jamaican Ovill McKenzie in October.

The Lebedev-Ramirez fight was elevated to the main event on the card in Moscow after the WBC heavyweight title fight between Deontay Wilder and Alexander Povetkin was postponed following a failed drug test for Povetkin.

On the undercard, Russia's Dmitry Bivol won the interim WBA light heavyweight belt in only his seventh professional fight on a unanimous decision against previously unbeaten Dominican Felix Valera.

-AP