“From what I understand it would appear part of the game was getting a bit heated,” he said.
The man was arrested at Penrith Police Station around 8pm on Sunday.
He has been charged with affray and assault occasioning actual bodily harm in the company of others and was refused bail to appear at Penrith Local Court on Monday.
On Sunday, NSW Police acting inspector Grant Morrissey said a brawl broke out and police allege one of the players stabbed an opponent and two spectators with a 15cm kitchen knife.
Police said the alleged offender then jumped in a car with other men and left the scene.
Two men remained in a critical condition at Westmead Hospital after being injured in the altercation. A 16-year-old boy was also treated for stab wounds on his arms after the incident.
A 19-year-old man was arrested in relation to the incident at a home at Cambridge Park at 2pm on Sunday. He had an existing hand injury and was taken to Nepean Hospital where he remains under police guard.
Mr Jobson said police planned to charge him with three counts of malicious wounding “as soon as [they] are able”.
He said police would be alleging the 19-year-old man was the “main offender” in the incident.
Investigations into the incident were ongoing.
In a statement on Sunday, NSW Rugby League chief executive David Trodden described the incident as “sickening”.
“Everyone who enjoys community sport at the weekend should expect to be able to do in a safe environment and it is nothing short of appalling that an incident like this has taken place in an area adjacent to where one of our matches was being conducted,” he said, adding that “anybody involved with the incident can expect never to have a role in our game ever again”.
Both teams have been stood down from the Parramatta Junior Rugby League competition pending the police investigation.
Mary Ward is a reporter at The Sydney Morning Herald.
Sally Rawsthorne is a Crime Reporter for The Sydney Morning Herald.