The lead singer of rock band The Zutons, who broke a man's nose after his girlfriend was insulted, was convicted of assault today.
Dave McCabe, 29, head-butted Peter Appleby during an alcohol-fuelled row outside a nightclub, Liverpool Crown Court was told.
McCabe, who wrote the hit song Valerie which was covered by Amy Winehouse and Mark Ronson, reacted after one of Mr Appleby's friends mocked his girlfriend's fur-collared coat, saying it looked like she had a beard.
The rock star denied assault occasioning actual bodily harm and claimed he had acted in self-defence.
The jury of five women and six men took three hours to unanimously convict the chart topper.
McCabe - whose songs include Please Calm Me Down and Havana Gang Brawl - looked disappointed.
Recorder Alan Conrad QC adjourned the musician's sentencing to October 29 for a pre-sentence report.
Mr Conrad said: "I am granting you bail but that is no indication of the sentence I will impose in this case."
McCabe, dressed in a suit and tie, asked from the dock: "Does that mean I can leave the country?"
Trouble started in the early hours of Sunday February 21 this year.
McCabe had attended his mother's 60th birthday party earlier in the evening then went with his girlfriend Sheree Grist to Korova nightclub in Liverpool with his brothers and friends.
The pair left at 3.30am and Mr Appleby and four of his friends also left the club.
Student Ciaran Donnelly, Mr Appleby's friend, said Miss Grist's fur-collared coat made it look like she had a beard.
The singer's girlfriend overheard and said to the group: "Why don't you grow up, you dickheads?"
Mr Appleby said the comment was private and was not supposed to be overheard by Miss Grist, who overreacted, he said.
"I didn't do anything to provoke him.
"I didn't intend to fight him.
"I was stunned when he headbutted me.
"I looked down and all I could see was blood."
The victim was taken by taxi to the Royal Liverpool Hospital where his broken nose was treated.
McCabe, of Vale Road, Liverpool, claimed he tried to defuse the situation by apologising for his girlfriend's comment but telling the group not to pick on them.
He said the five men surrounded him and he only headbutted Mr Appleby when it appeared the victim was going to attack him first.