WBC heavyweight champion Deontay Wilder delivered a seventh-round knockout to stop Cuba's Luis Ortiz in their anticipated rematch. (photo by Ryan Hafey)

Ortiz, who was clearly ahead on the judges' scorecards, when Wilder (42-0-1) stunned his opponent with a powerful right hand at MGM Grand in Las Vegas.

Wilder and Cuban opponent Ortiz initially met in March 2018, when the dangerous puncher stopped the 40-year-old in the 10th round.

Following six imperfect rounds on Saturday, Wilder came up big to abruptly end the bout against Ortiz (31-2) and stay undefeated with his belt on the line.

Wilder also etched his name into the heavyweight history books by making his 10th WBC title defence – equalling Muhammad Ali's record of consecutive defences.

"This is boxing," said Ortiz. "I said that one of us was going to get knocked out and it wasn't going to go 12 rounds. I was clear headed when I hit the canvas. When I heard the referee say seven I was trying to get up, but I guess the count went a little quicker than I thought.

"This was a great fight and I thought I was clearly winning. I got caught with a big shot and I have to give Deontay Wilder a lot of credit.  I knew my movement was giving him problems.  I landed some big shots and I thought I had him hurt.  I thought I was up by the count and could have continued.

"Deontay showed great will and I'm not ashamed with my performance. I know I can beat anyone in the heavyweight division. My career is not over. I'm going to work my way back into a big fight."