Police have appealed for witnesses following an attack in Bognor Regis town centre.
The 19-year-old man suffered a broken nose, broken cheekbone and an eye injury.
He was walking with his girlfriend close to the former Unicorn pub in the High Street around 5.30pm on Sunday, July 24.
They were set upon by a group of six men. The man was punched around the head, sustaining injuries which required hospital treatment.
Details were only released by the police today (August 4).
Anyone who witnessed the incident or has any information is asked to call Sussex Police on 0845 60 70 999 quoting serial 1686 of 24/07 or the independent charity Crimestoppers anonymously on 0800 555 111.