West Midlands Police have launched the investigation after the victim, who is in his 30s, was robbed at gunpoint outside the Railway Inn in Oldbury, near to Sandwell and Dudley railway station.
The incident happened at around 3.30am on Saturday, October 1 in a side street and saw a gang rob the man of a watch and leave him with an eye injury after he was struck in the face.
Police are asking for anyone with information which could help their investigation to get in touch.
A spokesman for West Midlands Police said: "We were called at around 3.30am today after a man was robbed of his watch by a group of men armed with a gun.
"The victim, in his 30s, suffered an eye injury when he was struck in the face during the robbery.
"It is believe to have happened in a side street near to The Railway Inn.
"Enquiries continue and anyone with information has been asked to get in touch quoting log 457 of 1 October."