Counties Manukau Police Senior Sergeant David Glossop said: "The scary thing as a police officer is, you know that one punch could have ended someone's life.
"He was unconscious for 15-minutes, the parents would have been hysterical after 15-minutes. People can end up with permanent brain damage as a result of this sort of crazy, spur-of-the-moment activity - there is no place for it."
The large scale brawl was not an isolated incident, said Mr Glossop.
"From a police point of view there is nothing new in this, it's a very sad state of affairs. It is good to see young people involved in sport but this has been happening for, the whole time I have been in the police I have been privy to it.
"There is no indication it is getting any more frequent, it is just sad that it is still happening."
Mr Glossop said the police investigation was still ongoing, and encouraged people who were involved or who witnessed the brawl to come forward voluntarily.
"We are still separating who are the offenders and who are the victims and who are the witnesses to the matter. We are seeking anyone who has CCTV footage or cell phone footage so we can get that evidence as well."
Auckland Rugby Union chief executive and former All Black Andy Dalton said the union was assisting police and its own judicial process through an independent committee was also underway.
It was understood the ARU was meeting with both schools this week to discuss the incident.
Otahuhu College principal Neil Watson said the school was involved in both investigations and the issue was addressed at an assembly today.
"This incident should not detract from the hundreds of [Otahuhu College] students and their families who play, watch and support sport every week."
Tangaroa College has not answered repeated requests for comment.
The incident comes just two weeks after an 11-year-old player allegedly tackled and punched a referee during an Under 12s game.
That child will face the judiciary next month, and could face a life ban from the sport.
