The Canberra Raiders and ACT Policing are investigating an incident allegedly involving player Bronx Goodwin in the early hours of yesterday morning.

ACT Policing confirmed last night that a 24-year-old Bruce man, believed to be Goodwin, was allegedly involved in two assaults outside All Bar Nun in O'Connor.

Fellow Raider Todd Carney is believed to have witnessed the brawl but is not under police investigation.

The incident occurred hours after the Raiders' memorable 34-12 NRL victory over the Sydney Roosters at Canberra Stadium.Goodwin did not play in that game.

He instead represented the Raiders' feeder club Souths Logan in Queensland on Saturday.Police attended All Bar Nun at 12.10am yesterday to investigate the brawl.

Several Raiders players had attended the venue to celebrate their win.

They had earlier been at the Dickson Tradesmen's Union Club for official post-game presentations.

An All Bar Nun staff member told The Canberra Times some of the players, including Goodwin and Carney, allegedly returned to the venue at midnight, about an hour after originally leaving. It remains unknown why they returned.

The incident is believed to have taken place between All Bar Nun and the nearby IGA Supermarket.

Raiders football manager David Sharpe confirmed he had been in contact with the police regarding the matter.

"Police have confirmed they are investigating an incident outside All Bar Nun on Monday morning, possibly involving one of our players," Mr Sharpe said.

"Something has happened but we are unaware of all the facts. It's being investigated and we're waiting to find out the nature of exactly what took place, who was involved and to what extent that involvement included."

When contacted by The Canberra Times Goodwin declined to talk.

"I can't say anything," he said. "I've been told I can't comment. I'm not commenting mate."

It is understood ACT Policing took statements from three people after the incident.