Jhonny Gonzalez defeated previously unbeaten champion Abner Mares in the first round to regain the World Boxing Council featherweight title in shocking fashion on Saturday.
Gonzalez was awarded a TKO victory after nailing Mares with a devastating left hook that floored the champion. Mares got up and continued to fight on the ropes but was knocked down again by a flurry of punches from Gonzalez. The referee stopped the fight at 2:55 of the opening round.
"I knew Mares was hurt and that sooner or later the fight would be over," Gonzalez said.
It was the first career loss for the 27-year-old Mares, who drops to 26-1 with one draw. Mares had won six straight fights since registering a draw against Colombia's Yonhy Perez in 2010.
Mares said he thought he could have continued.
"I was alright but the ref did his job and I respect that," he said. "You win some, you lose some. I am not in this sport to go and carry an undefeated record.
"I am going to take a break and enjoy my family and my kids."
Gonzalez improves to 55-8 with 47 knockouts, as he regained the crown he lost in September to compatriot Daniel Ponce de Leon, who Mares beat in May.
In an earlier bout on the undercard, Leo Santa Cruz pummelled Victor Terrazas with a third round knockout to capture the WBC's junior featherweight crown.
Referee Lou Moret stopped the fight at 2:09 of the third, with Terrazas defenceless and unable to see out of his right eye after being knocked down previously in the round.
The challenger dominated from beginning using his superior height and reach to land some heavy punches on Terrazas.
Santa Cruz said he won the title for his brother Roberto who is battling lupus, a disease which affects a person's immune system and attacks healthy cells and tissues.
"It means the world to me," said Santa Cruz. "I want to give the belt to (Roberto) because he is the real champion."
Santa Cruz vacated his bantamweight world title to move up to the junior featherweight ranks.
Terrazas falls to 37-3 with one drawn. Coming into the fight he had lost only once since his pro debut a decade ago. Saturday's defeat also snapped a 12-fight win streak.
