Two men were seen fighting at the Auctioneers pub in Northampton just before one of them was assaulted.
The assault happened between 2pm and 3pm on Friday (July 31), when two men were seen fighting by the Auctioneers pub.
They then walked across Market Square to Emporium Way, where another altercation took place and one of the men was assaulted.
A 47-year-old man was arrested in connection with the incident and has been released on bail pending further enquiries.
Witnesses, or anyone with information, are asked to call Northamptonshire Police on 101. Alternatively, they can call the independent charity Crimestoppers anonymously on 0800 555.