American Rolando Romero defeated Venezuela's Ismael Barroso on a controversial ninth-round stoppage to win the vacant World Boxing Association super lightweight title on Saturday.
Referee Tony Weeks stopped the bout at 2:41 of the ninth round in Las Vegas, Nevada, with Romero swinging but not landing against Barroso in the corner.
"He was a warrior. He wanted to keep going. He should have been able to keep going," Romero said after the victory. "I wanted to keep going. He wanted to keep going. We both wanted to keep going."
Instead, Romero improved to 15-1 with his 13th victory inside the distance, capturing a world crown in his debut at the 140-pound division.
Barroso, a 40-year-old southpaw, fell to 24-4 with two drawn, missing a chance to become only the 10th boxer to win a world title past his 40th birthday.
"I think it was an injustice to stop this fight," Barroso said through a translator. "I was giving the best shots."
Romero, 28, was knocked down for only the second time in his career by a punishing left to the head from Barroso late in the third round.
"I boxed the entire time," Romero said. "I came in a little cold, I got cracked and I finished the round like a champion and I kept going and I got the victory."
Romero was somewhat inactive for several rounds, being careful to avoid more punishing shots, the South American landing another hard left to Romero's head in the sixth.
"I took my time, moved around. The man is strong. I had to be careful with him," Romero said. "You think I wanted to get caught by one of those? I knew he could crack."
At the finish, Romero knocked down Barroso in the opening seconds of the ninth round, although Barroso called it more of a push down.
"The first punch is where I had him hurt," Romero said.
Romero began swinging wildly in the corner without success late in the round before Weeks stepped in to end matters.
"He just stopped the fight. He didn't tell me anything," Barroso said. "You could see it clearly. I was hitting him. There was nothing he was hitting me with clearly. I don't understand."
Romero had not fought since being knocked out a year ago by unbeaten he wanted a rematch with Davis or to US southpaw Gervonta Davis, but said fight Ryan Garcia, who lost to Davis last month.
Unbeaten Dominican Alberto Puello, 21-0 with 10 knockouts, was to have defended the title against Romero but he had an A-sample test positive for a performance-enhancing substance last month and was made a "champion in recess" on Wednesday.