Deontay Wilder successfully defended his WBC heavyweight championship against Gerald Washington.
American Wilder patiently waited for an opening, and got it early in the fifth round as he scored a technical knockout of Washington in Birmingham on Saturday.
The Alabama native moved to 38-0, with all but one victory by knockout, as he handed Washington (18-1-1) the first loss of his career.
While Wilder was patiently looking for an opening, Washington took advantage as the aggressor through the first four rounds at Legacy Arena.
Wilder found his opening early in the fifth round, knocking Washington to the canvas before the referee stopped the fight.
Washington, 34, was a defensive end at USC with practice squad stints in the NFL with the Buffalo Bills and the Seattle Seahawks, and did not make his professional boxing debut until 2012.
He appeared to be in control through the opening round, but a quick jab from Wilder's right hand to Washington's temple got the former football player unsteady before a left cross knocked him to the canvas.
Washington got to his feet, but was met with a barrage of punches from Wilder, prompting the referee to step in.
Wilder wants to unify the heavyweight belts and called out WBO champion Joseph Parker following Saturday's fight.
Former heavyweight champion Wladimir Klitschko will face undefeated British fighter and IBF champion Anthony Joshua (18-0) for the IBF and vacant WBA and IBO belts on April 29.
"I'm ready for Joseph Parker, but is he ready for me? I did my part, Joseph Parker," Wilder told Fox Sports in the ring. "Now it's time to do yours."