Man in hospital after Sydney CBD fight

A man is in hospital after a fight in Sydney's CBD early on New Year's Day.

Police say that at about 3am two men, both aged 22 and known to each other, were involved in an altercation when one of them fell and hit his head.

He was treated by NSW Ambulance paramedics before being taken to St Vincent's Hospital where he remains in a stable condition.

The second 22-year-old man was arrested but has been released pending further inquiries.