VIDEO: Ex-Boxing Champ Scores Stunning One-Punch KO From His Back in MMA Debut

The former WBO champion's violent finish may already be on the short list for MMA's Knockout of the Year.

Top Polish MMA organization KSW went all-in on putting together the promotion's second outdoor stadium card with KSW 83, and a heavyweight matchup between debuting fighters provided one of the year's most incredible finishes. 

KSW has never been shy about booking unique matchups, and one of the most intriguing fights from the KSW 83 prelims saw former WBO champion Krzysztof Głowacki take on experienced bare-knuckle fighter Patryk Tołkaczewski.

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Both fighters were making their respective MMA debuts at the packed PGE Narodowy in Warsaw, and Tołkaczewski appeared to have the upper hand when he secured full mount early in the fight before Głowacki landed a huge left hand from his back.

KNOCKED OUT from FULL MOUNT! 🤯

Former WBO cruiserweight champ 🇵🇱 Krzysztof Głowacki is dangerous from anywhere!!

XTB #KSWColosseum2 pic.twitter.com/7pZI71yaPX

— KSW (@KSW_MMA) June 3, 2023

Tołkaczewski slumped forward the moment the punch connected, and “Główka” quickly rolled to top position to land one more follow-up punch before running off to celebrate his first MMA victory. Głowacki had previously knocked out 20 opponents in the boxing ring as part of an impressive 32-4 record, but the sensational finish to his MMA debut might encourage the 36-year-old to return to the KSW cage sooner rather than later.

Głowacki previously capped off a five-fight run of victories by winning the WBO Interim World Cruiserweight Title in 2018, but since then he’s dropped three of four fights and was knocked out by Richard Riakporhe when he stepped into the boxing ring earlier this year. Prior to being knocked out at KSW 83, Tołkaczewski had only lost once via injury across eight boxing and bare-knuckle fights.

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The two debuting heavyweights provided some early entertainment on the prelims of KSW 83, and the event's main card also features a pair of title fights as well as another intriguing heavyweight clash with former pro boxer Artur Szpilka taking on KSW mainstay and former World’s Strongest Man Mariusz Pudzianowski.

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