Newly-released CCTV appears to show McGregor offering the grey-haired man a shot of Proper Twelve whiskey, which he founded and owns.
After the man rejected his offer, McGregor struck him in his face with a vicious uppercut.
Despite getting hit by the MMA star, the man remained on his barstool as McGregor was dragged away by stunned patrons.
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From TMZ Sports:
This is just the latest in a string of violent incidents involving McGregor.
A month ago, he was arrested for robbery and criminal mischief for destroying a fan’s phone in Miami.
Those charges were later dropped and he settled a civil suit with the victim.
Last year, he avoided felony charges in New York after breaking a bus window with a steel dolly, injuring several UFC fighters onboard the vehicle.
McGregor is also reportedly under investigation in Ireland after a woman accused him of sexual assault in December.
According to the New York Times:
Meanwhile, McGregor hasn’t fought in the UFC since October of 2018, when he lost to Khabib Nurmagomedov at UFC 229 in Las Vegas.