IRISH mixed martial arts superstar Conor McGregor has pleaded guilty in a Brooklyn criminal court to disorderly conduct, cutting a deal that allows him to avoid prison time over a New York brawl.

The 30-year-old, who is nicknamed “The Notorious,” had been charged with multiple counts of assault and criminal mischief after attacking a bus filled with Ultimate Fighting Championship contenders at the Barclays Centre in April.

The frenzied attack injured two athletes.

McGregor pleaded guilty to a lesser charge of disorderly conduct in a fleeting court appearance, and was handed a punishment of five days’ community service and an anger management program. All felony counts were dropped.

But he was served with “orders of protection,” to stay away from three people.

McGregor stood before the judge, looking sombre in a dark suit and striped tie, for the brief appearance.

“I just want to say I’m thankful to the DA (district attorney) and the judge for allowing me to move forward,” a visibly relieved McGregor told reporters outside the court.

“I want to say to my friends, my family, my fans — thank you for the support.”

“Now it’s about getting back to business,” said his manager, Audie Attar.

He had faced up to seven years in prison if convicted on all counts, and was released on $US50,000 ($A67,000) bail following his arrest.

Last month, following an earlier court appearance, McGregor expressed “regret” over the attack on the bus of rival fighters.

The Irishman pocketed around $US100 million ($A135,000) for the superfight he lost in August in Las Vegas against ex-welterweight champion Floyd Mayweather.

Their matchup was one of the richest boxing bouts of all time. McGregor is ranked fourth on the Forbes list of the world’s highest-paid athletes, with an estimated wealth of $US99 million ($A133 million), behind Mayweather in at number one, and soccer sensations Lionel Messi and Cristiano Ronaldo.

He was filmed lobbing a trolley through a window of the bus in a New York stadium at the end of a media event on April 5. The bus was moving slowly through the Barclays Centre loading dock at the time.

The father-of-one was also captured on surveillance cameras throwing a chair toward a passenger window of the bus.