What happened to Conor McGregor? Legend appears to blow out knee in opening round of comeback vs. Max Holloway

While MMA fans finally received their long-awaited wish to see Conor McGregor back in the cage, the joy was short-lived after the fighter went down with an injury in the opening round.

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Shortly after the opening bell, McGregor ran right at Max Holloway in the center of the Octagon. The Irishman threw an erratic, off-balance kick toward the Hawaii native, in which his right leg landed awkwardly and pushed forward, causing what many are calling an internal right knee injury. Dana White has stated his belief that McGregor injured his ACL in the mishap.

McGregor initially continued to power through the pain despite Holloway pleading with the referee to give his opponent time because he was visibly injured. However, «The Notorious» was unable to put any weight on that right knee and was forced to call it quits on his return.

Here’s the latest after The Notorious’ return ended early due to injury.

MORE: Full card highlights from McGregor vs. Holloway 2

What happened to Conor McGregor?

Holloway defeated McGregor with 3:54 remaining in the first round after the referee was forced to stop the bout. «The Notorious» could not continue due to an apparent knee injury, which the broadcast later shared was «a right internal knee injury.» After unleashing just one kick in the opening sequence, McGregor’s right leg awkwardly landed on the canvas. After that, the fighter was unable to put any sort of weight on his right leg, and eventually was forced to bow out of his return.

Here is a look at McGregor’s kick that caused his lingering injury.

RIGHT ON THE FIRST KICK 😳

Max Holloway gets his hand raised tonight!

[ #UFC329 | LIVE ON @ParamountPlus ] pic.twitter.com/8Y5MR1wJ4s

— UFC on Paramount+ (@UFConParamount) July 12, 2026

In the ensuing seconds, McGregor hobbled around the cage, with Holloway even asking the referee to stop the fight because the Irishman was obviously injured. Here’s when McGregor shook his head at the referee, and forfeited his long-awaited return into the octagon:

THIS FIGHT IS OVER IN ROUND 1 😳

Max Holloway defeats Conor McGregor!

[ #UFC329 | LIVE ON @ParamountPlus ] pic.twitter.com/fxSnBev6CM

— UFC on Paramount+ (@UFConParamount) July 12, 2026

A lone positive for McGregor was that tonight’s injury occurred on his right leg. In his most recent fight prior to tonight’s bout, McGregor broke a part of his left leg, so the damage may have been far more severe had it happened to his opposite leg. Here’s a look at McGregor walking out after his defeat:

Conor McGregor is walking with a limp after his apparent leg injury. pic.twitter.com/vdEAQ4GFLu

Read more Social media reacts to Conor McGregor injuring knee in opening moments of return fight vs. Max Holloway

— ESPN (@espn) July 12, 2026

According to UFC CEO Dana White, McGregor’s outlook is far from promising. «We’re assuming blown ACL,» White said during the postfight press conference. «The doctors think the same thing too.»

🚨 Dana White’s immediate reaction to Conor McGregor’s injury:

«I was expecting AT LEAST a one round war… We’re assuming blown ACL. The doctor’s think the same thing too.» #UFC329 pic.twitter.com/yQ5AXEumhD

— Championship Rounds (@ChampRDS) July 12, 2026

At the moment, there is no official diagnosis for McGregor’s exact injury. That said, the Nortorious One did weigh in hours after the conclusion of the fight via Twitter.

My head gasket is gone. Destroyed. I had no injury / injuries going into the fight. I was throwing kicks, planted and jumping, all throughout camp as well as backstage before the fight. This came out of nowhere. I am beyond dark here. I can only describe it as hell.

— Conor McGregor (@TheNotoriousMMA) July 12, 2026

MORE: McGregor vs. Holloway 2 full card recap: Who won every fight?

Conor McGregor injury history

This is not the first time The Notorious has been injured inside the Octagon. Here is McGregor’s injury history:

Will Conor McGregor ever fight again?

At the moment, it does not look likely that McGregor will ever step foot into the Octagon again. The former all-time great appears to have another road to recovery ahead after injuring himself for the second-straight fight.

At this stage of his career, tonight’s fight was most likely McGregor’s final time strapping into the gloves in the UFC.

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MORE: Why is Conor McGregor called «The Notorious?»