Footage has emerged of UFC star Conor McGregor appearing to punch an elderly man in an Irish bar.

The incident happened at The Marble Arch Pub in Dublin on April, according to TMZ.

Their report claims that McGregor walked in and lined up cups for bar patrons as he prepared to buy a round of his Proper Twelve whiskey.

However, the guy refused after McGregor placed a cup in front of him, not once but twice.

McGregor downed a shot with other drinkers and then unexpectedly threw a left fist at the man.

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The UFC star, who hasn’t fought since losing to Khabib Nurmagomedov at UFC 229 last October, was pulled out of the bar.

The attack was reported to the police, who said in April that they would open an investigation. There are, however, no reports that McGregor was charged, and it’s unclear if the investigation is still active.

Notice the guy's reaction. Or lack of one. He barely bats an eyelid.

It's not the first controversial moment of McGregor's career.

He dodged felony charges in New York last year after smashing a bus window with a dolly, resulting in several UFC fighters onboard the vehicle suffering injuries.

And in May, he smashed a phone out of a fan's hand in Miami. 

The former UFC lightweight and featherweight champion was arrested for robbery and criminal mischief, but the charges were eventually dropped.

It's unclear when McGregor will return to the octagon after nearly a year away.

“I don’t know,” UFC president Dana White said about McGregor's return, per MMA Junkie. “That, I don’t know.

"See how Saturday goes, see how September goes, and then see what happens with Conor.”