Francesco Facchinetti, who is a DJ from Italy, said MMA fighter Conor McGregor broke his nose with a punch to the face.
TMZ Sports reported that Facchinetti said the punch happened at approximately 2:30 a.m. Sunday and was unprovoked in front of 10 witnesses.
"I took a punch for nothing," the DJ said. "That punch could go to anyone. My friends, my wife, or other friends. That's why I decided to sue Conor McGregor because he is a violent and dangerous person."
Simon Samano of MMA Junkie noted Facchinetti said he and his wife, Wilma Helena Faissol, were spending time with McGregor and the fighter's fiancee, Dee Devlin, when the punch occurred.
Faissol posted the following on her Instagram Stories (h/t TMZ Sports):
"Then out of nowhere, he threw a punch in the face of Francesco. He was inviting us to another party. Francesco said, 'Okay, let's go' and he hit him. Luckily, he [Francesco] was very close so he [Conor] couldn't load up on his punch. Francesco flew back, fell on the table, and then on the ground. The first thing that came to mind was 'are we kidding? Is it a show?' Then I was paralyzed.
"I turned around and saw that his friends were holding him against the wall because he wanted to continue beating Francesco. Then they took him away. I turned on the light and the guards turned them off. Francesco was bleeding. I wanted to help him and the guards chased us away."
This is far from McGregor's first altercation outside of the Octagon.
Samano noted he had something of a "scuffle" with musician Machine Gun Kelly and actress Megan Fox on the VMAs red carpet.
McGregor's last fight in the Octagon for the UFC was when he lost to Dustin Poirier in July.