A former UFC light heavyweight title challenger scored a cold-blooded one-punch KO at a behind-closed-doors event in Las Vegas

• Ovince Saint Preux returned to the light heavyweight division with a highlight-reel left hook knockout.
• "OSP" had previously campaigned in the UFC's heavyweight division, losing a decision to Ben Rothwell in May.
• At the UFC Apex in Las Vegas on Saturday, the Haitian-American finished his opponent Alonzo Menifield in the second round.
• He paid tribute to the recently deceased "Black Panther" Chadwick Boseman, then said he'd be ready to fight again next week.
• Watch the finish below.

A former UFC light heavyweight title challenger scored a cold-blooded one-punch KO at a behind-closed-doors event in Las Vegas, then paid homage to the late "Black Panther" actor Chadwick Boseman.

The 205-pound match between the former title challenger Ovince Saint Preux and Alonzo Menifield served as the chief support to Alistair Overeem's main event victory over Augusto Sakai at the UFC Apex on Saturday.

After a heavyweight stint in which he lost a decision to Ben Rothwell in May, Saint Preux returned to light heavyweight this weekend and produced a show-stopping performance with a dominant win over Menifield.

Saint Preux threw 42 strikes at Menifield in the first round and 38 in the second, and it was the last — a pinpoint left hook to the jaw — which ended the bout with 55 seconds left on the clock.

The shot was so powerful all the American could do was collapse in an instant and face-plant the canvas.

Watch the single-shot finish right here:

Or here if you're in a different region:

Saint Preux didn't even pounce on his fallen opponent as he knew, just standing over him, that the fight was over.

He then took a few steps, stopped, and posed with the "Wakanda Forever" salute to the superhero actor Boseman, who died from colon cancer aged 43 on August 28.

After the win, he said on the ESPN broadcast that he was eager to get back into the Octagon to compete as soon as possible. "Hmmm … let me think about it. Let's try next week. I'm trying to get another fight definitely this year."

Saint Preux advanced his record to 25 wins (12 knockouts, eight submissions, and five decisions) against 14 losses.

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