Undefeated American heavyweight Deontay Wilder stopped former Olympic champion Audley Harrison in the first round Saturday night at Motorpoint Arena.
Harrison fell in a neutral corner from the first meaningful punch of the bout, and Wilder kept flailing at him before referee Terry O'Connor stepped in and called it off after 1 minute, 10 seconds.
Wilder, the 2008 Olympic bronze medalist, improved to 28-0, all by knockout.
Harrison, who briefly held a minor world title nine years ago, fell to 31-7. The American admitted it was likely the end of his career.
''I've got to be realistic, I'm 41. It's going to be hard to get opportunities like this on the big stage again,'' Harrison said.
The fight was on the undercard of the Amir Khan's welterweight bout against Julio Diaz.