The main event of UFC 329 had so much potential.

In Conor McGregor’s return after five years away from the Octagon, it was assumed that his fight against Max Holloway, ultimately, could lead to two possible outcomes. Following the bout, McGregor could with a win add his name to the already loaded list of top contenders in the lightweight (or welterweight) division or move on to final fight on his UFC contract.

Unfortunately, the match ended in the only way that could leave fans with more questions than answers.

McGregor announced Sunday that he injured his right ACL and meniscus during a flying kick attempt seconds into the fight. It was the second consecutive McGregor fight to end unsatisfyingly early because of a non-contact injury. Before UFC 329, McGregor had not been in the Octagon since July 2021, when he broke his left tibia and fibula taking an awkward step backward in the first round of a trilogy fight against Dustin Poirier. To make matters even worse, McGregor was set to return from the broken leg against Michael Chandler in 2024 but was forced to back out after he fractured his left pinky toe during training.

Inconclusive results for marquee fights are not the norm, but in the five years between McGregor’s leg injuries, there have been a handful of promising fight cards capped off by anticlimactic main and co-main events.

That list of disappointing endings includes a pair of championship fights that ended without a victor, a couple of bizarre injuries and an ultra-rare occasion in which a headlining bout was canceled during the event in progress.

Welterweight: Conor McGregor vs. Max Holloway 2

Event: UFC 329 main event, July 11
Result: Holloway wins by TKO

In a year that already had provided fight fans with the returns of MMA pioneers Ronda Rousey and Gina Carano, it seemed only right that the biggest MMA star of all, McGregor, would add his name to the list. After he backed out of the Chandler fight in 2024 just 16 days before the fight was scheduled to take place, there was plenty of doubt about whether McGregor would actually return.

McGregor proved the doubters wrong, showing up at the event and making the walk to the Octagon. But that’s where the story turned. The injury to his right leg happened during the first strike he threw at Holloway. McGregor valiantly attempted to keep fighting after he was hurt, but the referee stopped the fight less than a minute later, and Holloway was awarded a TKO victory.

The injury now leaves McGregor in limbo. He has said he will undergo surgery on his leg in the near future and wants to fight again next year. Questions remain about his post-surgery recovery timeline, though. Will UFC 329 go down as the last time the UFC’s first double-champion was seen inside the Octagon?

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Joshua Van grabs victory after Alexandre Pantoja breaks arm

Event: UFC 323 co-main event, Dec. 6, 2025
Result: Van wins by TKO

Van, one of the UFC’s fastest rising young stars, earned his first UFC title shot at UFC 323. His opponent, Pantoja, is one of the most dominant champions in UFC men’s flyweight history and entered the fight on an eight-fight winning streak that included five title fight victories. This was expected to be a very tough test for Van, but it didn’t turn out that way.

Pantoja suffered an arm injury early in the opening round of the fight. After a couple of striking exchanges to open the fight, Pantoja attempted a head kick, but his leg got caught on Van’s shoulder. Van shrugged it off and pushed Pantoja to the canvas, where the then-champion injured his elbow trying to catch his fall. The fight was called 26 seconds in. Van was declared the winner and new champion by TKO.

Van successfully defended the title against Tatsuro Taira at UFC 328 in May, which could lay the foundation for a potential rematch against Pantoja in the near future.

Event: UFC 321 main event, Oct. 25, 2025
Result: No-contest

This was one of the most disappointing outcomes to a title fight in UFC history, and the result still looms large over the UFC’s glamour division.

Aspinall, who had been the UFC’s interim heavyweight champion for nearly two years while waiting for an opportunity to unify the titles against Jon Jones, had finally been promoted to undisputed champion following the announcement of Jones retirement last June. Without the opportunity to prove his mettle against the UFC’s GOAT, Aspinall would have to make the most of an opportunity to defend his championship status against Gane. The expectations for Aspinall were sky high, and a win would likely legitimize his standing as the top heavyweight in MMA.

Instead the fight ended in a no-contest due to an incidental eye poke by Gane. Before Aspinall was injured, the bout had all the makings of a competitive matchup. Gane, who closed as a +275 underdog according to DraftKings Sportsbook, proved to be a dangerous, worthy opponent for Aspinall, going back and forth with the champion in an all-striking affair. The competitors had nearly identical striking statistics in both volume and accuracy, but it was Gane who drew blood first, catching the champion with a straight right hand to the nose. Just as Gane began picking up steam, an inadvertent eye poke late in the first round rendered Aspinall incapable of continuing the fight.

The damage from the eye poke was so significant that Aspinall underwent multiple surgeries earlier this year on both eyes to repair double vision and insufficient eye movement. He announced on social media last month that he has returned to “full training,” setting up a possible rematch with Gane, who impressively defeated former two-division champion Alex Pereira in June to claim an interim title.

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Maycee Barber says more tests needed after medical event

Event: UFC Fight Night, May 31, 2025
Result: Canceled

Blanchfield and Barber entered the weekend as two of the top-ranked contenders in the women’s flyweight division, and a noteworthy performance in this fight could have propelled either fighter to the front of the line for a title shot. But moments before their walkouts, it was announced that the fight had been canceled because Barber had suffered a medical emergency backstage and was transported to the hospital.

In an interview with Uncrowned, Barber said that despite missing weight for the fight, she felt fine while rehydrating, then the medical emergency happened while she was warming up backstage.

“Everything was great. I felt good on fight day,” Barber said. “And then I was warming up, and to be honest, that’s really all that I remember is warming up, and then I remember being in the back of an ambulance.”

Barber returned to the Octagon six months later, earning a unanimous decision win over Karine Silva at UFC 323 in December 2025.

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Alexa Grasso keeps flyweight belt after split draw

Event: Noche UFC main event, Sept. 16, 2023
Result: Draw

Grasso pulled off one of the biggest upsets in UFC history at UFC 285 in March 2023, beating Shevchenko by fourth-round submission to claim the women’s flyweight championship. The highly anticipated rematch was booked six months later, and the fight lived up to fans’ expectations.

Both fighters had their moments in a closely-contested, five-round bout. Shevchenko used a grappling-heavy approach, scoring four takedowns and racking up more than eight minutes of control time, while Grasso leaned on her boxing background, dropping Shevchenko with a hard straight right hand in Round 2. However, 25 minutes of action wasn’t enough time to determine a winner, as the judges scored the fight a split draw (48-47, 47-48, 47-47). Because the fight ended in a draw, Grasso kept the title.

The inconclusive result of the rematch ensured fans would see a trilogy bout, and hopes were high for another exciting fight. The rubber match took place a year later at the 2023 Noche UFC event, and this time the result was much more definitive. Shevchenko dominated Grasso to earn a unanimous decision win and reclaim the belt.

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Jan Blachowicz, Magomed Ankalaev fight to split draw

Event: UFC 282 main event, Dec. 10, 2022
Result: Split draw

Before the controversial result in the Grasso vs. Shevchenko 2 title fight, there was a similar outcome in a fight for the vacant light heavyweight championship at UFC 282.

Following the announcement that Jiří Procházka was vacating the 205-pound title due to injury, the UFC announced that former champion Blachowicz and first-time title challenger Ankalaev would square off for the belt in the main event of the last pay-per-view event of that year.

Although the stage was set for the winner of this bout to enter the new year atop a division with a few fresh matchup possibilities, neither fighter managed to do enough to get a win on the judges’ scorecards. Blachowicz severely battered Ankalaev with leg kicks that nearly rendered Ankalaev unable to stand on multiple occasions. Ankalaev’s answer with significantly more striking volume. He landed 191 strikes to Blachowicz’s 79 and mixed in grappling, recording more than 11 minutes of control time.

The fight was scored a split draw by the three judges, who all saw it differently (48-47, 46-48, 47-47). During the postfight news conference, UFC CEO Dana White expressed frustration with both fighters’ showings. “I think the main event was terrible,” White said. “I started to zone out after like three f—ing rounds.”

Heavyweight: Curtis Blaydes vs. Tom Aspinall

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Blaydes in disbelief after Aspinall’s early injury

Event: UFC Fight Night, July 23, 2022
Result: Blaydes wins by TKO

Entering this fight card held at O2 Arena in Aspinall’s home country of England, there was a feeling that the main event against Blaydes would be Aspinall’s opportunity to cement himself as the top contender for the heavyweight championship. The British rising star was undefeated inside the Octagon, riding a five-fight win streak and seeking a third consecutive win over an established UFC veteran.

Aspinall was aggressive from the start, landing a big knee, mixing in punches and throwing a pair of kicks before the fight was suddenly stopped after just 15 seconds. On his third kick attempt, Aspinall injured his right knee and fell to the canvas, wincing in pain. Aspinall suffered a torn MCL, torn meniscus and damaged his ACL. The injury kept Aspinall out of action for 364 days.

He finally got the chance to avenge his first UFC loss by taking on Blaydes again two years later at UFC 304. This time, the stakes were even higher, as Aspinall’s interim heavyweight title was on the line. Aspinall made quick work of Blaydes, beating him by first-round knockout in exactly 60 seconds.

Lightweight: Dustin Poirier vs. Conor McGregor 3

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McGregor injures leg in Round 1, Poirier wins by TKO

Event: UFC 264 main event, July 10, 2021
Result: Poirier wins by TKO

Following a TKO loss to Poirier just six months earlier, McGregor was back in action against the fellow fan favorite in a trilogy match.

McGregor came out aggressively, putting Poirier on the back foot with a series of leg kicks and spinning kicks to open the fight. Then, Poirier gained momentum, backing up McGregor with a series of punches that forced McGregor to clinch.

Poirier scored a takedown moments later and established top position, where he landed vicious ground-and-pound strikes. Just when it seemed as if the round would end with the fighters grappling on the canvas, they separated and returned to their feet with 15 seconds left in Round 1. As the two traded punches and kicks in the final seconds, McGregor threw a punch with his right hand, and as he stepped to put his weight back on his left leg, he crumbled. McGregor had broken his left tibia and fibula, and Poirier was awarded a TKO victory.