Despite convincing wins over South Africa and England in their opening two games, the Ferns have not been entirely convincing in their performance.
Their turnover count has topped 20 in both outings - well above the demanding standards Waimarama Taumaunu sets her side.
New Zealand's struggles for consistency mean it did not looking the firm favourite it was heading into the series after its historic win over Australia in last month's Constellation Cup.
The Diamonds are missing several top players from last month's series, with Natalie Medhurst, Julie Corletto and Laura Geitz all taking time off for rest and rehabilitation but, given the Ferns' most recent form, you would have to put the two sides back on level pegging ahead of tomorrow's match-up.
Having scored a major breakthrough against Australia with the Constellation Cup win, when they recorded their first series success over the Diamonds in eights years, the Ferns are determined not to lose the ground they gained on the world champion.
"I think as soon as you hear the words Australia everyone picks up their game and has that much more focus," New Zealand captain Casey Williams said.
Australia too is fiercely motivated for the clash of the Quad Series heavyweights after the Ferns' 2-1 series win last month.
"We don't like to lose," Diamonds coach Lisa Alexander said. "There's no better way to get fire in the belly than not accepting that and making sure we address all the issues we needed to address.
"So we're very hungry heading into [tomorrow]."
Despite the Australian line-up being quite different from that which took the court in the Constellation Cup, Taumaunu expects the Diamonds will be as competitive as always.
"Australia have such great depth that they are able to call on players with test experience as replacements," she said.
Compared with the upheaval in the Australian team, the changes to the Ferns' line-up appear quite minor, but these have made a significant difference to their attacking dynamic.
Without midcourter Camilla Lees, who was impressive against Australia last month, the Ferns are a little light on options.
Bailey Mes has struggled to find her feet at wing attack in her first two tests against South Africa and England and, as such, Taumaunu will be wary about throwing her on against Australia.
The other combination the Ferns have been trying out is not exactly ideal either, as it means moving the world's best centre, Laura Langman, into wing attack to accommodate Kayla Cullen at centre.
By Dana Johannsen.
