Australia have blown a five-goal lead to lose 53-52 to the Silver Ferns in the first Test of netball's Constellation Cup in Christchurch.
A dominant third quarter on Sunday put the Diamonds ahead 44-39 but a series of errors quickly evaporated their advantage.
The match was the first between the teams since July's World Cup final in England where the Silver Ferns upset the Diamonds 52-51.
Diamonds coach Lisa Alexander said it was frustrating to watch her team's lack of attention to detail in the crunch moments.
"I think we went away from some areas of our game plan that we had made a commitment to do," she said.
"And got a little bit sucked in to the environment that was going on around us and that will be a learning, particularly for the new players, that they can't let that distract them."
The final quarter steadily worsened for Australia, who also lost goal shooter Caitlin Bassett. She left the court in discomfort and was replaced by Caitlin Thwaites.
Bassett was one of Australia's best, shooting 26/30 before leaving the game.
The four-Test series will move to Auckland on Wednesday and Alexander said her captain would be "cherry ripe" for game two.
The Diamonds found themselves down 26-25 at half-time after a poor opening half in which they were unable to capitalise on turnover ball.
Australia, who hold the Constellation Cup, were particularly wasteful in the attacking third as their connections from the midcourt to the shooting circle were rusty.
Alexander brought Laura Scherian on for her Test debut late in the second quarter and she was more efficient when feeding the shooting circle.
"She's just reminded us about how accurate she is with her feeding and the work that she does. She's enormous in there. It was terrific to see her out there," Alexander said.
But that fluidity went out of the Diamonds' attack in the final quarter and the Silver Ferns regained the lead with seven minutes to go and never gave it back.
After Auckland, the series heads to Australia for Tests in Sydney and Perth.
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