The sporting world did a collective face-palm when footage emerged of Conor McGregor punching an elderly drinker.
Ever since his historic victory over Eddie Alvarez in late 2016, the Irishman has spent his time either losing fights or hitting the back-pages for all the wrong reasons.
There are questions as to whether the fame has gone to McGregor's head and losses to both Floyd Mayweather and Khabib Nurmagomedov have done little to change that verdict.
And aside from a slew of incidents that include stamping on a fan's phone, the latest footage to emerge of the Irishman might be the most damaging yet.
A CCTV reel from the Marble Arch pub in Dublin, filmed on April 6, was released recently that showed McGregor greeting fellow patrons while taking a seat at the bar.
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McGregor involved in punching incident
Holding a bottle of his Proper No. Twelve whiskey, McGregor started putting glasses down for people to try, only for one man to cause tension by lifting the cup away.
The gentlemen eventually made a gesture to shoo away McGregor who, after pouring three drinks and clinking glasses with those around him, threw a punch to the side of the drinker's head.
Remarkably, the old man remained completely calm on his stool, while McGregor was dragged away from the scene.
Drinker criticised McGregor's whiskey
And now sources at the Irish Mirror have provided even more details on the incident, revealing the exact comment that provoked McGregor into taking such violent action.
The informer explained: “The fella McGregor offered a drink to said, ‘I don’t want to drink that s**t, I don’t want your drink’ and McGregor wasn’t happy.
"And sure that was the end of it – then he swung for him. I’m told when he has a few [drinks] in him he can get hyper. As far as I know he hasn’t been in touch with the pub since it all happened.
"It happened back in April. It was stupid and maybe the man should have just passed the drink on to someone else and just thanked him.”
All in all, it was a petty disagreement then. The man probably should have been more courteous about refusing the drink, but it was a gross overreaction from McGregor to take the action he did.
A separate source from April also added: “There was a bit of a commotion, [McGregor] was acting the mick and there was an incident.
“The man that was allegedly assaulted is from Ballyfermot and drinks in the pub a good bit.”
The Sun are reporting that McGregor is set to be charged for the alleged assault, which first emerged on TMZ, and will appear at Dublin District Court to address the incident.
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