"Witnesses to the dancefloor incident were able to alert the bar manager and staff followed a man who left the bar for a short time so were able to provide valuable information to us,'' said Detective Senior Sergeant John Sutton.
"Being able to monitor real-time CCTV footage in the area enabled staff in our district command centre to dispatch officers to a Fort St car park promptly which resulted in the 22 year-old's arrest.
"Once again, as if any further proof was needed, this event shows nothing good happens in the city after 3am.''
It was originally reported by police and ambulance that the injured person was a woman.