Usher allegedly beat up a man in a club on New Year's Eve (31.12.14).

The 36-year-old singer is reported to have been partying at Miami nightclub E11even when a man insulted his girlfriend - and rumoured fiancee - Grace Miguel, leading to him losing his temper and punching him repeatedly.

A source told MediaTakeOut.com: ''Usher was in VIP with his girlfriend, and some drunk White guy was screaming disrespectful things towards Usher, trying to get his attendtion. When that didn't work, we started saying nasty things about his [fiance Grace]. The guy called her ugly...

''To Usher's credit, we didn't act like a b*tch. He broke through security and started fighting the guy. (sic)''

The source goes on to claim the 'Climax' singer punched the unidentified man multiple times like a ''boxer''.

The eyewitness continued: ''Usher f**ked him up. It was like a four piece - Usher must be a boxer or something because the punches were very fast.''

Potentially in response to the incident, the musician - who has sons Usher, seven, and Naviyd, six - posted a photo of a painful eye injury on Instagram on Friday (02.01.15).

Captioning the image, he wrote: ''You should see the other guy!! (sic)''

Referencing the photo, the source added: ''I don't know how Usher's eye got like that because I didn't see White dude even tough Usher. (sic)''