1. Old Man Punch
By the far, the worst confirmed incident in the past few years was when McGregor punched a 50-year-old man in Dublin’s Marble Arch pub. To sum up, he tried to buy a round of his whiskey for everybody in the bar but the older man rejected it twice. McGregor reacted violently.

He lashed out with a sucker punch that bounced off of the man’s skull. Fans greeted his action with derision and contempt. This was a new low for McGregor and he swiftly broke a media silence to apologize because he realized he had gone too far. After facing assault charges, the Irish court fined him for his pathetic action.