Terence Crawford retained his WBO welterweight title and extended his unbeaten record to 34 wins with a 12th-round stoppage of Jose Benavidez Jr.
Crawford, 31, sent his fellow American to the canvas with a sharp right-hand uppercut with less than a minute left.
Benavidez Jr recovered but the fight ended in flurry of punches from Crawford, with the referee stepping in.
Crawford kept his pre-fight promise of not shaking Benavidez Jr’s hand after the bout in Nebraska.
There had been bad blood in the build-up, which culminated in Crawford trying to punch Benavidez Jr at Friday’s weigh-in.
“It feels so good to shut somebody up who’s been talking for so long,” said Crawford, who was making the first defence of his title since winning the belt against Australian Jeff Horn in June.
The home favourite told ESPN: “I did what I said I was going to do. The knockout was coming. It was just a matter of time. He slowed down tremendously. He was tired, and once he slowed down, I saw I could catch him with the uppercut.”