Police are appealing for witnesses to an assault outside a fast food restaurant in Bognor Regis.
The 24-year-old man was attacked outside the Peri Peri House on Waterloo Square at 4.10am on Sunday, July 15.
The victim spoke to the suspect, who he didn’t know, who then punched him breaking his jaw.
The suspect is described as white, 5ft 11ins, medium build and around 25.
He has short dark hair and was wearing a dark short sleeved t-shirt, blue denim jeans and white trainers.
He left in the direction of The Esplanade.
Detective sergeant Mark Gowling said: “This is quite a nasty and unprovoked assault with the victim now needing a surgical operation to repair the damage.
“We are appealing for witnesses who might have been in the Peri Peri House at the time or anyone who knows the man to ask him to come forward.”
If anyone saw anything they are asked to contact Sussex Police on 101 quoting serial 1639 of 15/7 or the independent charity Crimestoppers anonymously on 0800 555111.