He was set to face Michael Chandler in what would have been his first fight since losing to Dustin Poirier at UFC 264 three years ago. 

A new main event has been announced, with Alex Pereira defending his UFC light heavyweight title against former champion Jiri Prochazka, but MMA fans will be disappointed that one of the sport's biggest names will not be returning to the Octagon in the near future. 

Why did Conor McGregor vs. Michael Chandler get cancelled? 

In a post on X, UFC president Dana White announced that Conor McGregor vs. Michael Chandler at UFC 303 will not be happening after McGregor pulled out with an injury. 

"Conor McGregor is out of UFC 303 with an injury," White said. 

"It has been a crazy week here at UFC."

Even before it was confirmed that McGregor vs. Chandler was not going ahead, there were concerns surrounding the Irishman after he was filmed partying into the early hours during fight camp. 

These concerns were then heightened after a pre-fight Dublin press conference on June 3 was cancelled at the last minute and since then speculation was rife as to whether the clash would go ahead. 

Since the announcement about McGregor's injury, no recovery timeline has been given while Chandler will no longer feature on the card in Las Vegas. 

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