Stephen Donegan, of Shanballymore sustained serious head injuries from the incident in Concert Square in the early hours of Saturday morning and is in an induced coma at a Liverpool hospital.
It is believed the 24-year-old, from was visiting the city to attend the Liverpool versus Blackburn Rovers FA Cup tie on Sunday afternoon.
Mr Donegan was discovered lying in an alleyway, near to the Walkabout Bar and Level nightclub. Detectives have recovered CCTV footage and are seeking witnesses.
Members of his family are believed to be travelling to be at his bedside.
Kyle Harley, 19, from Birkenhead, has been charged with grievous bodily harm in relation to the attack after presenting himself at a police station on Sunday.
Appearing at Liverpool magistrates court he made no plea and was released on conditional bail. He will appear before Liverpool Crown Court on March 23.