Washington - American Adrien Broner stopped Britain's Ashley Theophane in the ninth round on Friday in a victory that left the World Boxing Association super lightweight title vacant after Broner failed to make weight.
The fight at the DC Armory went ahead, and Broner, a four-division world champion, dominated.
Theophane, who could have taken the title with a victory, was on the ropes in the second round, and absorbed punishing blows that had one eye swelling by the fourth.
He rallied, landing some solid punches in the sixth, seventh and eighth, but Broner had him under pressure again in the ninth with a body shot and a right hook.
Theophane was backing up and had raised a glove - possibly to complain of a low blow - when referee Luis Pabon stopped the fight.
"I always could do better but I did what I had to do to get the victory," said Broner, who improved to 32-2 with 24 knockouts while Theophane fell to 39-7 with one drawn and 11 knockouts.
The technical knockout punctuated a turbulent fight week, with US media reporting that Washington DC boxing officials agreed to license Broner after he vowed to surrender to authorities in Ohio, where police have issued warrants for his arrest on suspicion of felony assault and aggravated robbery.
The charges stem from an incident on January 21 in which Broner allegedly robbed a man after an altercation outside a bowling alley in Cincinnati.
Broner was scheduled to make the first defence of the junior super lightweight world title he won with a 12th-round knockout of Russian Khabib Allakhverdiev in October.
But Broner registered 140.4 pounds (63.68 kg) at Thursday's weigh-in, 0.4 pounds over the division limit and he was stripped of the title.
In compensation Broner agreed to pay $50 000 from his purse to Theophane, who weighed on the 140-pound limit.
"I've been going through a lot this whole week and to come in here and bottle everything up and stay focused and get it done, I want to give a pat on the back to myself," Broner said before turning his attention to retired pound-for-pound king Floyd Mayweather, a co-promoter of the bout.
"Somebody I look up to and somebody I admire talked all bad about me," Broner said. "Me and Floyd, we got a feud."
With Mayweather laughing at ringside Broner challenged him.
"I come from nothing and I will never let a man disrespect me," said Broner. "He got to come see me. We got to get it on."