Mikey Garcia stopped Juan Manuel Lopez in the fourth round on Saturday night, leaving the WBO featherweight title vacant after Garcia failed to make weight.
Garcia (32-0) weighed in at 128 pounds on Friday, two over the featherweight limit. Lopez weighed in at 1251/2.
Lopez (33-3) would have regained the title with a win.
Garcia put Lopez on the ground with a strong left-handed blow 1:34 into the fourth round for his 27th career knockout.
Garcia won the title from Orlando Salido on a unanimous decision in New York on Jan. 19. The title reign, however, was short-lived after Garcia didn’t make weight.
The only two losses of Lopez’s career were to Salido. The first one cost him the WBO belt, and the second led to a one-year suspension by Puerto Rican boxing officials when he accused the referee who stopped the fight of betting on the match.
Lopez had won twice since his one-year ban ended, beating Aldimar Silva Santos in February and knocking out Eugenio Lopez in an undercard bout in Mexico City in April.
With a majority of fans chanting his name early, the 25-year-old Garcia came out and landed a series of jabs in the first round.
In the second round, Garcia knocked Lopez down with a right cross in the second round. Lopez quickly rose to his feet and completed out the round. Garcia finished off the 29-year-old Lopez two rounds later.
Lopez appeared wobbly early in the fourth after Garcia landed a combination of punches.
Garcia finished him off with a powerful left cross. Lopez slowly got up and referee Rafael Ramos quickly called the match.
On the undercard, Terence Crawford (21-0) won the vacant NABO lightweight title, stopping Alejandro Sanabria (34-2-1) in the sixth round. Crawford dropped Sanabria with a left hook 17 seconds into the round.
Sanabria got up, but the referee called the fight to give Crawford his 16th knockout victory.