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Conor McGregor celebrates after defeating Jose Aldo in their featherweight championship bout during the UFC 194 event inside MGM Grand Garden Arena
Fight Coverage

Most Shocking Knockouts In UFC History

Looking Back At Some Of The Most Unexpected Finishes Inside The Octagon

There’s a lot that goes into a result being shocking: fandom, betting, or weeks and weeks of expectations pointing toward something else. Regardless of the reason why, some results sent shockwaves throughout the entire MMA world, as very few could’ve predicted what they saw on screen.

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While this isn’t an all-encompassing list of every shocking moment ever, here are a few standouts worth a rewatch this holiday season:

Conor McGregor KOs José Aldo In 13 Seconds

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 Conor McGregor punches Jose Aldo in their UFC featherweight championship bout during the UFC 194 event inside MGM Grand Garden Arena on December 12, 2015 in Las Vegas, Nevada. (Photo by Christian Petersen/Zuffa LLC)
Conor McGregor punches Jose Aldo in their UFC featherweight championship bout during the UFC 194 event inside MGM Grand Garden Arena on December 12, 2015 in Las Vegas, Nevada. (Photo by Christian Petersen/Zuffa LLC)

Okay, sure, if you were to ask an Irish MMA fan in 2015 for their prediction of this fight, some might have said a one-punch knockout. But putting bias aside, not many people truly believed it would happen. Many UFC fighters and journalists alike didn’t see McGregor pulling off the win at all.

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At the time, Aldo had won 25 of his last 26 fights and was the only featherweight champion in UFC history, a title he had defended seven times prior to this clash with McGregor. Unfortunately for Aldo, a rising superstar was bulldozing his way up the division during his reign, and when he was finally met with the thunderous left hand that had finished so many before him, Aldo too had fallen. The win propelled McGregor from MMA star to worldwide sensation and set the stage for some of the biggest moments in UFC history.

Jorge Masvidal Flying Knee KOs Ben Askren

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Jorge Masvidal knees Ben Askren in their welterweight fight during the UFC 239 event at T-Mobile Arena on July 6, 2019 in Las Vegas, Nevada. (Photo by Josh Hedges/Zuffa LLC)
Jorge Masvidal knees Ben Askren in their welterweight fight during the UFC 239 event at T-Mobile Arena on July 6, 2019 in Las Vegas, Nevada. (Photo by Josh Hedges/Zuffa LLC)

At UFC 239 in 2019, which featured both Jon Jones and Amanda Nunes successfully defending their titles, the biggest storyline of the night was a fight that lasted just five seconds. Former BMF champion Jorge Masvidal and Ben Askren had been chomping at each other for weeks, building excitement for what many expected to be a long, thrilling matchup between an elite striker and a decorated wrestler.

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What happened, however, was something still unmatched to this day. As soon as the fight began, Masvidal circled ever so slightly to his right, then charged at Askren, who dipped his head straight into a flying knee that knocked him out cold before the fight clock was even on screen.

Rose Namajunas Head Kick KOs Zhang Weili

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Rose Namajunas kicks Zhang Weili in their UFC women's strawweight championship bout during the UFC 261 event at VyStar Veterans Memorial Arena on April 24, 2021 in Jacksonville, Florida. (Photo by Josh Hedges/Zuffa LLC)
Rose Namajunas kicks Zhang Weili in their UFC women's strawweight championship bout during the UFC 261 event at VyStar Veterans Memorial Arena on April 24, 2021 in Jacksonville, Florida. (Photo by Josh Hedges/Zuffa LLC)

Something was in the air when UFC returned to a full-capacity crowd at UFC 261 following the pandemic. It was as if the MMA gods wanted fans to witness every possible outcome on a single card, and that’s exactly what happened in Jacksonville, Florida. Seven knockouts, two submissions and a gruesome leg injury combined to make one of the most memorable events in the promotion’s history.

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The most unexpected moment of the night, however, came in the co-main event, a strawweight title fight between then-champion Zhang Weili and Rose Namajunas. Just over a minute into the contest, Namajunas uncorked a left high kick that landed flush on Zhang’s chin. A few ground-and-pound strikes later, Zhang was out, and Namajunas had reclaimed the strawweight throne.

Leon Edwards Come-From-Behind KO vs Kamaru Usman

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Leon Edwards lands a head kick to Kamaru Usman in the UFC welterweight championship fight during the UFC 278 event at Vivint Arena on August 20, 2022 in Salt Lake City, Utah. (Photo by Chris Unger/Zuffa LLC)
Leon Edwards lands a head kick to Kamaru Usman in the UFC welterweight championship fight during the UFC 278 event at Vivint Arena on August 20, 2022 in Salt Lake City, Utah. (Photo by Chris Unger/Zuffa LLC)

What has become one of the most iconic moments in UFC history was, at the time, seconds away from being one of the more forgettable main events of 2022. Not to discredit Kamaru Usman in the slightest, who for the majority of UFC 278’s main event had completely dominated Leon Edwards, but it was so one-sided that many might have left Vivint Arena disappointed with the outcome.

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That was until Edwards flipped the script and flatlined Usman with a head kick knockout to claim the welterweight title with less than a minute to go in the fifth round. Following commentary suggesting a decision loss might be Edwards’ best possible result, Jon Anik famously remarked, “That is not the cloth from which he is cut,” words that perfectly captured one of the greatest come-from-behind victories inside the Octagon.

Israel Adesanya Exacts His Revenge vs Alex Pereira

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Israel Adesanya knocks out Alex Pereira in the UFC middleweight championship fight during the UFC 287 event at Kaseya Center on April 08, 2023 in Miami, Florida. (Photo by Cooper Neill/Zuffa LLC)
Israel Adesanya knocks out Alex Pereira in the UFC middleweight championship fight during the UFC 287 event at Kaseya Center on April 08, 2023 in Miami, Florida. (Photo by Cooper Neill/Zuffa LLC)

It’s hard to imagine what losing your UFC title to a bitter rival feels like. While most MMA fans know the full story by now, UFC light heavyweight champion Alex Pereira defeated former middleweight champion Israel Adesanya twice in professional kickboxing, then hunted him down in the UFC and scored a fifth-round TKO to steal the title out from under him. Safe to say, that didn’t feel good.

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However, all that defeat makes for a more poignant story when Adesanya finally earned redemption at UFC 287. Pereira entered their rematch with the confidence of a reigning UFC champion and three wins over Adesanya already behind him. While Adesanya was by no means out of the fight, Pereira looked sharper and more in control than in their previous encounter, which he still won. As Pereira began finding his rhythm late in the second round, pushing Adesanya back against the fence, “The Last Stylebender” unleashed two right hands that sent Pereira crashing to the canvas. Regardless of your feelings toward either gentleman, this was a shocking knockout and a powerful moment for Adesanya, who conquered a mountain only he believed he could.