Gervonta Davis remained undefeated in handing Mario Barrios his first loss on Saturday, while Vasyl Lomachenko cruised to victory in his return to the ring after losing his lightweight title belts last fall.
Davis (25-0) claimed Barrios' WBA super lightweight title with an 11th-round TKO in Atlanta, becoming a world champion in a third different weight class.
Davis dropped Barrios (26-1) with a hard left to the body with just over a minute remaining in the penultimate round, but the Texan managed to regain his feet.
A quick left to the face by Davis immediately after the restart staggered Barrios and led the referee Thomas Taylor to end the fight.
The victory allowed Davis to add the super lightweight strap to the WBA lightweight and super featherweight belts he already holds.
In Las Vegas, Lomachenko (15-2) defeated Masayoshi Nakatani (19-2) by TKO in the ninth round after a dominant showing throughout the contest.
It was his first fight since losing by unanimous decision to Teofimo Lopez in their lightweight unification bout on October 17.
Fighting without a world title at stake for the first time since his professional debut in 2013, Lomachenko did what he needed to do against the Japanese fighter, who also had dropped a decision to Lopez.
The Ukrainian pounded on his taller opponent from the opening bell and appeared to have taken each round handily before the referee stopped the fight following a flurry of shots by Lomachenko.