Police are seeking a man and a woman who may have witnessed a late-night assault in Nelson.

The victim was left shaken after the alleged assault which took place on Collingwood St around 11pm on Friday, January 9.

Police said they were interested in talking to the pair who they believe saw the incident which left the victim with serious injuries.

They appealed for the potential witnesses, or anyone that held any information about the incident to contact them online or by phoning 105.