A 20-year-old man suffered a broken jaw and teeth after he was attacked in a Sheffield city centre bar.
The man was at the bar in Code on Devonshire Street, when was punched by another male in an unprovoked assault.
Police said the incident happened at around 2.30am on Sunday, November 30.
Officers would like to speak to anyone who may have been in the club around the time of the attack, or anyone who witnessed the incident.
n Contact police on 101, or Crimestoppers on 0800 555111, quoting incident number 172 of November 30.