Police are appealing for witnesses to an assault on Saturday night.
It happened at about 8.30pm at Clinches Celtic Tavern on North Quay, Douglas.
A man received serious facial injuries and needed hospital treatment.
A 25 year old man from Willaston was arrested and is helping police with their enquiries, but Sergeant Gary Heaton from the Douglas neighbourhood policing team still wants to speak to anyone who has information on the incident, or who was in the pub at the time.
Sergeant Heaton can be contacted on 631423.
Alternatively you can ring Police Headquarters on 631 212 or the anonymous Crimestoppers line, on 0800 555 11.