More than a dozen fans attempted to invade the pitch in the final stages of Friday night's NRL win by the Warriors against the Newcastle Knights at Wellington's Sky Stadium.
The match was delayed by several minutes as security attempted to wrangle the fans off the pitch.
The invasions delighted the 16,676-strong crowd, with cheers as the fans avoided security with side steps and jagged runs across the field.
However, Sky Stadium chief executive Shane Harmon revealed the dangerous side of the light-hearted tradition.
"Four got on the field with around seven minutes to go and then we had another large group around fulltime and just after the final whistle," he told AAP.
"We had two security guards injured. One was transported to hospital with suspected concussion, and that's the point for me where enough is enough.
"We need to act before there is an incident which changes the sport in New Zealand forever."
Harmon says invasions are becoming more common, more organised and more dangerous.
"I don't believe that they see themselves putting people at risk but we've had issues with people jumping over the fence and breaking a leg," he said.
"It only takes one incident ... if that was a player at the weekend, it would be major, major news."
Eden Park chief executive Nick Sautner shared Harmon's fears.
He said an incident could "potentially jeopardise the future of large-scale international events" in the country.
"We strongly discourage any crowd behaviour, including pitch invasions, which puts anyone at risk of being hurt," he told AAP.
"While Eden Park is known as the fortress, we certainly don't want to be installing perimeter fences around our turf to guarantee the safety of the players and staff."
Friday night's pitch invaders have been banned from Sky Stadium for two years and given formal warnings by police.
Under New Zealand law, fines of up to $5000 or three months imprisonment are possible for pitch invaders - but only for designated major events such as last year's Rugby World Cup and this year's FIFA Women's World Cup, co-hosted with Australia.
Harmon said he wanted to see a law change to see hefty fines, such as those levied in Australia, available to all sporting codes.
"I have no desire to see courts and police time clogged up by so many idiots acting inappropriately," he said.
"My understanding of speaking to venues in Australia is that the $5500 fine (as used in NSW) has been a major deterrent."
Sport minister Grant Robertson said he would consider proposals for change.
"To hear two people were seriously hurt out of (the NRL game) is really shocking," he told AAP.
"I'm aware the fines in Australia are larger than here.Â
"I'm sure that's something that could be contemplated, but for the most part it works. So I don't want to catastrophise."
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