Mr Facchinetti called the police following the incident at the five-star St Regis Hotel.
He claimed The Notorious – who has been named in Forbes’s annual list as the highest paid athlete in the world with €180million in earnings – punched him in the mouth, broke his nose in front of 10 witnesses, his friends and bodyguards.
He alleged the Dubliner attacked him without motivation after they talked for more than two hours.
Mr Facchinetti claimed: “I could have shut up and not said anything to anyone, but since I’m here to tell it, I must say that that person is really violent and dangerous. If McGregor’s lawyer were to call me tomorrow and offer me €10million to withdraw the complaint and to withdraw everything, I would say no.”
And he told his local radio station Radio 105 on Wednesday: “I don’t care about money, I don’t care about hype.
“That is a highly dangerous man, seeing him in front of your eyes is another thing than reading about him.”
McGregor could face from three months to three years in prison in Italy if he is charged and convicted of the assault.
The country also uses fines along with imprisonment as a form of punishment.
The Irish Mirror has contacted McGregor’s representative for a comment on the incident but as of last night, no reply had been received.
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