Witnesses are being sought to a violent attack upon a 48-year-old man outside the Lord Byron Pub in Kingsley Park Terrace, Northampton.
A verbal altercation took place between a man and two women and he left the area briefly but returned to continue the argument.
Another man then left the pub garden to intervene and try and prevent any violence, at which point he was struck by the first man, causing swelling to the face and a cut to the back of the head.
The attacker then left the pub and walked in the direction of Collingwood Road, Abington.
He is described as being mixed race, 20 to 30-years old, between 5ft 3ins or 5ft 4ins, medium build, short black hair and wearing a short black bomber jacket.