Former Australia international Megan Anderson says questionable coaching moves cost the Diamonds dearly in the first Constellation Cup Test against New Zealand on Sunday.
The Silver Ferns won the first Test by two goals, 54-52, on the back of an outstanding game by goal attack Maria Tutaia, who dominated Laura Geitz in an unfamiliar role as goal defence.
The victory gives the Silver Ferns a 1-0 lead in the best of three series, with the next two matches to be played in New Zealand.
Anderson said Diamonds coach Lisa Alexander's decision to play Geitz away from her more familiar position at goal keeper was a mistake.
"I do question some of the changes that Lisa made, but I haven't been in the training camp so I don't know how everybody's playing," she told BigPond Sports Weekend on Sunday after the match.
"Definitely putting Geitzy out at goal defence, I would not have expected that and I don't think that's her best position.
"When you've got someone like Maria out there, you would want to have a specialist goal defence on there to hassle the hell out of her the whole game.
"It was too easy for her out there tonight and she doesn't like it when someone's in her face. That's really what you needed tonight and I don't think they chose the right option there."
Sydney Swifts star Carla Dziwoki agreed with Anderson's assessment, noting that Geitz's switch to keeper where she stood dangerous veteran Irene van Dyk sparked Australia's revival.
"It changed it up putting Geitzy back in goalkeeper. I think she gave Tutaia a bit too much room at goal defence. That changed the momentum and also putting (Caitlin) Bassett into goal shooter, Australia were able to up their scoring rate," she said.
The Silver Ferns entered the match as underdogs and boasted a squad undergoing generational change after the retirement of Temepara George and absence of defender Joline Henry through pregnancy.
However, they didn't miss a beat with relative newcomer Camilla Lees slotting in particularly well.
"Lees did just enough to help out the big three. You've got Irene van Dyk, Maria Tutaia and Laura Langman there so you don't really need to be a superstar amongst those people," Anderson said.
"You just need to fit in and assist them in what they're doing and I think she did that really well."
The victory leaves the Silver Ferns well placed to claim their first Constellation Cup but Anderson said the Diamonds were more than capable of reversing their fortunes in the second Test, to be played on Thursday in Auckland.
"These girls play against (their NZ opponents) now often enough to know that it's (about) getting into the game straight away and not letting go for that quarter before you actually get used to the zone.
"It's really just going back and concentrating on the basics and getting the pass and cut happening so that you break up the zone a little bit easier."