Eleven players and a supporter have been charged by the NSW Rugby League following an under-18s match that descended into a violent brawl in Sydney’s south-west.

The disciplinary action relates to an incident after The Oaks Tigers and Campbelltown Collegians Under-18s Gold Division match at Dudley Chesham Sports Ground on Sunday.

The NSWRL said two Campbelltown Collegians players had been charged with assault or acting aggressively towards another person, bringing the club or league into disrepute, and breaching the code of conduct.

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A further eight Campbelltown players have been charged with breaching the code of conduct, while one The Oaks Tigers player has been charged over his involvement in a fight after the match.

A supporter from The Oaks Tigers has also been charged over a social media post.

“The matter is still being investigated by police and both the Campbelltown Collegians and The Oaks Tigers Under 18s Gold Division teams remain stood down,” an NSWRL spokesperson said.

“NSWRL has a zero-tolerance policy towards anti-social behaviour and will make no further comment until the police investigation is complete.”

NSW Police said officers were called to the sports ground following reports of a brawl between players and spectators after the match.

A 71-year-old man was taken to hospital with rib and face injuries requiring treatment.

According to 7NEWS reporting at the time, the fight allegedly began after a late penalty sparked an argument before spilling into the car park.

The injured man was allegedly assaulted after trying to help a family member.

“It’s just out of control. They just attack anyone,” a supporter from The Oaks, who asked not to be identified, told 7NEWS.