Ant McPartlin of TV duo Ant and Dec was punched in the face while watching football with his mates at his local pub in West London.
The attacker shouted “Where’s your girlfriend?” before belting him at The Barley Mow pub in Chiswick.
The jibe apparently referred to Ant’s comedy partner Declan Donnelly.
Eyewitness Giedrius Kudzinskas told The Sun: “Ant didn’t react and this bloke launched himself at him and punched him in the face.
“Ant reeled back and then a big fight broke out as his mates came to help him. Other people jumped in and held back the other guy.
“The bloke was thrown out but when Ant left later, he was waiting for him. There was another lot of shouting and then Ant walked off.
“It was all totally unprovoked.”
Giedruis added: “He was furious about what he had said to him.”
The thug was described as wearing tracksuit bottoms and a beanie hat. The Geordie TV presenter had been watching the Barcelona v Arsenal match when the attack took place.