Thames Valley Police is appealing for witnesses following an assault in Reading.
The incident took place around 11pm on Saturday 1 June in the outside area of the Victoria Arms on Victoria Road, Mortimer.
The offender head butted the victim, a 24-year-old man, after they began to engage in conversation.
The victim sustained a cut to the face and was treated at the Royal Berkshire Hospital. He has since been released from hospital.
The offender is described as a white man, in his twenties and approximately 5ft 10ins tall with light brown hair. He was wearing a Tottenham football shirt with a bomber jacket.
Investigating officer, PC Craig Thomas based in the Incident and Crime Response team at Newbury police station, said: “I am appealing for anyone who witnessed this incident to come forward, as they may have information vital to our investigation.
“Anyone with information about this incident should report the details on the Thames Valley Police website quoting reference 43190165075. Alternatively, you can call the non-emergency telephone number, 101, or contact the independent charity Crimestoppers anonymously on 0800 555 111.”