A video released on social media earlier in August appeared to show the Irishman punching a man in the head inf the Marble Arch pub in Dublin.
But in an interview with ESPN, the 31-year-old says that watching the video back is “like a dagger into my heart.”
“I must take accountability and take responsibility,” McGregor said.
“It doesn’t matter what happened there — I was in the wrong. That man deserved to enjoy his time in the pub without having it end the way it did.”
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Accepting his punishment
The matter is under investigation by police and McGregor, who announced his mixed martial arts retirement in March, says he will accept whatever punishment is handed out.
“Whatever comes my way, I will face it,” McGregor added. “Whatever comes my way, I deserve it. I will face this head on. I will not hide from it.
“I must be calm. I must be Zen. I must lead by example. I need to get a hold of this, and I am working very hard to do this.
“I am taking the necessary steps.”
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The incident in Dublin took place a month after McGregor was arrested for allegedly smashing a fan’s phone in Miami, USA.
Florida prosecutors dropped all charges against the Irishman, after saying the accuser stopped cooperating and the state could no longer prove the charges.
McGregor says he hopes to learn from his problems for the benefit of the people around him.
“I have been making amends to be better – to be a better father, be a better human, to be a better role model to these kids,” he said.
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“I have to realize that is not the attitude or behavior of a leader, of a martial artist or a champion. I must get my head screwed on and get back in the game, fight for redemption, retribution, respect – the things that made me the man I am.
“I was completely in the wrong. It was unacceptable behavior.”