American Gary Russell dominated Jhonny Gonzalez en route to a fourth-round technical knockout on Saturday to seize the Mexican's World Boxing Council (WBC) featherweight world title.
Gonzalez had no answer for Russell's speed and power.
Russell knocked down Gonzalez three times in the fight - once in the third round and twice in the fourth, with referee Tony Weeks calling a halt less than a minute into the round.
"This is the kind of performance I expect, but you can't get these every time," said Russell, who was making his second bid for a world title after losing in June to Ukrainian southpaw Vasyl Lomachenko in a World Boxing Organization title bout.
"We put the work in at the gym. We grind three times a day, hard," said Russell, who indicated after the fight he wants a rematch with Lomachenko.
Russell knocked Gonzalez down with a big left-right combination at the end of the third round, Gonzalez regaining his feet just as the round ended.
Russell opened the fourth by landing a flurry of blows to Gonzalez's head and body, a left to the head sending him down again.
Gonzalez rose but was clearly hurt when the action resumed, and another flurry from Russell sent him down again and had Weeks stepping in.
Russell, a 2008 Olympian, improved to 26-1 with 15 knockouts while Gonzalez fell to 57-9 with 48 wins inside the distance.
Gonzalez was making his third defense of the title he won for the second time in 2013.
Gonzalez first won the crown in 2011 but lost it in 2012 when an accidental head-butt brought an eighth-round end and a loss to Daniel Ponce de Leon in Las Vegas.