A terrified 9-year-old football player ran from the field crying after being verbally abused by an opposition player's parent who threatened to "rip" the child from the pitch.
The parent's club has apologised "unreservedly" for the incident and launched an investigation.
However, Cailean Hamilton, who feared he would be physically harmed by the irate father, hopes some good will come from the incident and is calling for sideline spectators to check their behaviour at kids' sport.
It comes after the country's five biggest sporting codes vowed to make major changes to how children play sport , taking the focus away from just winning.
Cailean Hamilton was pulled aside by the parent before the final of a North Shore tournament and handed some stern words about a previous incident.
"They had a friendly match seven months ago and while the game was going on the parent, my son was marking theirs, said he 'nearly elbowed' his son," Cailean's mother, Katie Hamilton, said.
"Elbows happen 20 times a game. The kids are 9, they're running and they can't control what happens. But it wasn't even an elbow, it was a nearly.
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"He's been saving this up for seven months till he got to this tournament and attacked my son about it. We don't even remember it happening."
Cailean was told if he went near the parent's child, he'd come onto the field and rip him away, "it was pretty scary for him".
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The match took place at a football tournament in Birkenhead between Cailean's Under 10 side, Fencibles United AFC, and the opposition, East Coast Bays AFC.
Cailean was shaken by the incident, as was his team, who were all scared by the outburst and ended up losing the match, Hamilton said.
"I was too scared to tackle him during the game and couldn't play the game properly," Cailean told the Herald.
"I was playing with my friends when he came up to me before the game to warn me to not go near his son.
"I was so scared when he was telling me he would rip me off the pitch and I ran to Dad crying."
But it wasn't only Cailean, his team and their supporters shocked by the spray, but also the East Coast Bays coach who addressed the incident.
The coach threatened to pull his team from the match and told the parent off, Hamilton said, adding the club had apologised for the behaviour as well.
East Coast Bays coach Russell Fisher, a club board member, told the Herald a full and thorough investigation had been launched.
Upon completion, the board would then decide what action to take against the parent who verbally abused Cailean.
"What we have done so far is apologised unreservedly both on the day, and in writing to the coach concerned," Fisher said.
"I feel that the club Fencibles have behaved in an impeccable way and have handled themselves with complete dignity, on the day and subsequently.
"I really do believe they are beyond reproach in the way that they've handled this issue … I respect them very much for that."
Fisher reiterated it was no way to act and the club was disappointed the incident took place.
Following the final whistle, the parent attempted to apologise to Cailean but it was not enthusiastic or heartfelt, Hamilton said.
"He said, 'I'm sorry for saying that, but you need to stay away from my kid'. So it wasn't really an apology.
"My son was already scared he was going to hurt him physically and the rest of the team were worried about it too."
Rubbing salt to the wound, Cailean had written a school speech about negative sideline behaviour and coaching before the incident took place.
Following the match, he was inspired to share his speech about sideline behaviour on the day, recording a video and uploading it to YouTube.
"The parents are quite hard on some of the kids because they're in a rep grade," his mother said.
"They don't think about them being 9 and they just want them to win all the time.
"[Cailean] sees the boys crumble, from any team, under their pressure and it's really hard for him."
Harassment from the sideline was not okay, it took away all the fun from playing the game and could force them to stop, Cailean said in the speech.
"Competitive sport is fast and tough, and we need to make very quick decisions. We really do need all the positive support we can get, no negative vibes please."
A report of the incident had not been reported to the Auckland Football Federation (AFF) as of Monday afternoon, a spokesperson said.
"AFF has a zero-tolerance to reported and proven incidents which break the NZ Football Code of Conduct which all members are bound by.
"Our disciplinary process is there to provide sanctions against violations of the code of conduct should they occur."
AFF helped facilitate education on the purpose of community sport, such as the "Keep Up with the Play" initiative launched on Monday by Sport NZ.
NZ Football was among New Zealand Cricket, Hockey NZ, Netball NZ and New Zealand Rugby who all signed an agreement to change the way kids play sport.
They wanted sport in the country to be more inclusive and not only focus on the winners.
Proposed measures included changing the competitive mindset of adults, reviewing regional and national tournaments and how teenage talent is identified.