Three people have been charged after a fight outside a Sydney bar overnight.

About 1.15am, emergency services were called to a night club on Bayswater Road, Potts Point, following reports of a brawl.

Police report a 21-year-old man was assaulted when he tried to break the fight up.

The man was knocked unconscious after being punched in the head.

He was treated at the scene by paramedics and taken to St Vincent’s Hospital.

Officers from Kings Cross Command arrested two men, aged 19 and 20.

The 19-year-old was charged with assault and the 20-year-old was charged with assault and property damage.

Both men received bail and will attend Downing Centre Local Court on August 21.

A third man, aged 22, was arrested at the scene and issued a court attendance notice for a later date.   

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