LAS VEGAS — Deontay Wilder stunk out the joint, throwing few punches and showing little passion during the first six rounds of his WBC heavyweight title bout with Luis Ortiz at the MGM Grand Garden Arena.

It was more of the same in the seventh.

But when you punch like Wilder, all it takes is one and that one came in the waning seconds of the seventh round. Wilder landed a crushing straight right to the head that dumped Ortiz like he’d been shot. Ortiz got up on unsteady legs and referee Kenny Bayless stopped it.

It kept alive a planned February rematch with lineal champion Tyson Fury that was in doubt as Wilder inexplicably held his fire and didn’t pressure Ortiz. Nearly all of the good punches that landed were thrown by Ortiz, and it was so bad for Wilder at times that the crowd began chanting the Cuban born Ortiz’s name.

But Wilder has that home run punch which has led him to 41 knockouts in 43 fights and he landed it at the right time Saturday. The time of the finish was 2:51 of the seventh.

“I buzzed him with the left hook and that was the start of it,” Wilder said. “Ortiz is one of the best in the world.”

Wilder said he needed to move in and out to set up his shots and that in the seventh, “I finally found my measurement.”

Ortiz said he was clear-headed and wanted to continue, but it was obvious he was in bad shape and Bayless undoubtedly made the right call.

It guaranteed that Wilder could keep his date with Fury, which will be a huge fight both in terms of significance within the division and financially. For a while, though, it was slipping away as Wilder simply kept the guns in the holster most of the fight.

But his power is rare even in the division where most of boxing’s big punchers have lived. All he needs is one and he showed that on Saturday when he knocked Ortiz out for the second time in as many years. Wilder stopped Ortiz on March 2, 2018, at the Barclays Center in New York in their first meeting.

Wilder said in the ring Saturday that after fighting Fury, he wants to unify the belts. IBF-WBA-WBO champion Andy Ruiz will defend his titles on Dec. 7 in Saudi Arabia against the man he took them from, Anthony Joshua.

“We need one champion, one face, one name,” Wilder said.

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