Police are referring a 15-year-old boy to their youth aid section, after a brawl at a weekend rugby match that left another unconscious.
The boy was knocked out in the fight at a game between Otahuhu College and Tangaroa College last month.
Police said after a lengthy investigation, which involved interviewing a large number of people, they have established who they believe was responsible for throwing the punch which injured him.
Counties Manukau West Area Commander Jason Hewett said police force was working closely with Auckland Rugby Union over the matter.
"In this case I expect much higher standards of the parents and the spectators -the adults - that were there and it sets a very poor example for our young people."
He said young men should be able to play the sport without it descending into violence.
Meanwhile, the Auckland Rugby Union's independent Judicial Committee met last week to review the abandoned match.
The panel ruled that the referee was justified in calling off the match and that neither team would receive competition points.
A fine was imposed on both teams, which is refundable if specific conditions are met.