Wellington Rugby Union and club officials are investigating claims that racial abuse sparked a brawl between Marist St Pats and Old Boys University players and supporters.
The fight broke out in the final moments of the tense encounter at Wellington College, when OBU fans reportedly invaded the in-goal area, after their team had scored the winning try.
An MSP player became involved and the situation escalated from there.
"It is clear some of our players became upset following repeated, highly disturbing racial slurs and the attack on the father of one of our players by an intoxicated group of OBU supporters," claims MSP chairman Rob Evans.
"Just as violence cannot be tolerated, the kind of racial abuse witnessed on Saturday has no place in our game."
Newshub has approached Old Boys University for comment, but Wellington Rugby chief executive Matt Evans has told Stuff that his staff is examining video scouting footage to determine how the brawl began.
"We're moving heaven and earth to make sure we get a robust disciplinary process up and running," he says. "It's really important we send a strong message.
The Marist St Pats club was disqualified and copped a three-year ban from Wellington Rugby's annual sevens tournament, after a Petone opponent was hospitalised by a brutal attack last November.
Matt Evans tells Stuff the incident raises concerns over club culture at the respective clubs.
"If they're prepared to turn a blind eye and tolerate these things, maybe things are out of whack."