Australian fans say they were spat at and bombarded with vitriol at the weekend - as Rugby World Cup insecurities twisted the friendly transtasman rivalry into hostility.
"The biggest shame for me, my wife and a lot of Australian fans is the atmosphere seemed really great for all the other nations - Kiwis seemed embracing of everyone except someone wearing a gold jersey," said Wallaby fan Phil Dunne, from Sydney.
Mr Dunne arrived in Auckland on Friday and left on Monday. He had never expected a soft ride from New Zealanders, but the hatred crossed a line, he said.
"Some of the charming exchanges involved sexual comments about my wife, instructions on how we could all f*** off back to Australia and even included one charming bloke attempting to spit on us."
The experience was mirrored by many other Aussie fans he had spoken to on the night, Mr Dunne said.
"I think the hate vibe given off by New Zealanders towards us is so entrenched at this World Cup that most Kiwis don't even realise how hostile they actually are."
Another Australia fan said there had been pockets of genuine unpleasantness at Eden Park.
"A Kiwi, dressed in Irish green, shouted to a group of Australian fans 'It's not mardi gras you f*****g poofters'."
Earlier in the tournament, Government minister Maurice Williamson raised eyebrows for his boisterous opposition to the Wallabies in a corporate box he shared with members of the Australian Rugby Union.
Sydney Morning Herald columnist Spiro Zavos, who was born in New Zealand, commented that the ministerial behaviour was an indication of anti-Wallaby feelings among New Zealanders.
The hatred hinged on Wallaby Quade Cooper because of his "stupidity in continually trying to bait Richie McCaw", Zavos wrote after the Saturday match.
"The animosity to Cooper, in fact, went much further than just booing him ... a spectator a couple of rows behind me screamed out: 'Smash him! Kill him! Kick him in the head!'," he said.
Australia has become the team New Zealanders least want to see win the World Cup, according to a Herald-Digipoll survey - despite the country's extensive help through the Pike River and Christchurch earthquake tragedies.
Victoria University associate professor of Psychology Marc Wilson said the souring of the Anzac brotherhood was driven by the insecurities Kiwis felt "deeply, pathologically and perversely about this bloody World Cup".
"Nationally, there's a monkey on our back and it's not just a game right now," Dr Wilson said.
New Zealand saw itself as the "runty one" compared with our bigger neighbour, the Wallabies' recent good form had made us worried, and even Australia's strong economy contributed to jealousies.
But our attachment to the All Blacks was a big factor, Dr Wilson said.
"New Zealand is no different from any other country in the world ... we associate with things that make us feel positive about ourselves," he said.
AUT's dean of Applied Humanities and associate director of the Tourism Research Institute, Nigel Hemmington, said it was easy for good-natured ribbing to turn unsavoury.
"We are the hosts for the Rugby World Cup, not the hospitality industry, the whole of New Zealand. We should be honorable and hospitable to our guests," Dr Hemmington said.
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