Australia has one hand on netball's version of the Bledisloe Cup after a final quarter meltdown saw New Zealand fall to a five-goal loss at a sell-out Adelaide Entertainment Centre on Sunday.
Silver Ferns shooters Irene van Dyk, who had five uncharacteristic misses, and Maria Tutaia (20/27) crumbled at the death after holding a one-goal lead as Australia stormed home to take the final stanza by five-goals and the match 48-43.
Australian coach Norma Plummer will trim her Commonwealth Games squad from 15 to 12 on Monday, one of the first names she pens will be aggressive defender Susan Fuhrmann. After coming on in the last quarter, Fuhrmann upset the Ferns shooting pair which turned the match her side's way.
Diamonds captain Sharelle McMahon led from the front, nailing 24/26 in her second match back from injury while New Zealand skipper Casey Williams was outstanding.
Over 9000 fans packed in to witness the opening match of the three-Test series which marked the 50th anniversary of New Zealand's first seven-a-side tour of Australia. The occasion introduced the 101 diamonds-encrusted Constellation Cup that will be annually contested between the two fierce trans-Tasman rivals.
New Zealand stole Australia's opening centre-pass to take a 3-0 lead, but after a slow start Diamonds defender Mo'onia Gerrard twice tipped van Dyk's shot to claw her side back.
The Silver Ferns blew their more settled look as Australia locked it up at 12-all at the end of the first quarter.
Several questionable calls from the neutral umpires and 12 turnovers cost New Zealand in the second period of the contact-heavy match. Five misses from their shooters, to the home side's three, saw them slip behind.
McMahon formed a short-sharp shooting combination with Natalie Medherst (24/30) and the captain held a blemish-free record at half time, which meant Australia pulled away to a two-goal advantage, 23-21.
With Australia treating the match as a trial, it came as a surprise when Ferns coach Ruth Aitken made four changes and her opposition made none for the third period.
In a bid to spark her stuttering mid-court, Aitken sent Liana Barrett-Chase to wing-attack, Temepara George to centre, Laura Langman replaced Joline Henry at wing-defence and Leana de Bruin pushed Katrina Grant out of the defensive circle.
The changes worked, providing the impetus for a comeback. Barrett-Chase looked strong and George more comfortable as the ball flowed to Tutaia and van Dyk better.
New Zealand snuck into their final huddle 36-35 ahead after winning the penultimate quarter 15-12.
But crafty Plummer introduced the combative Fuhrmann for the run home. Her long reach and in-your-face approach rattled Tutaia and van Dyk, who missed a shot that saw Australia take a three-goal lead with five minutes to play.
New Zealand's shooters cracked under the intense caldron pressure, both missing crucial attempts to draw closer. The Diamonds, by contrast, grew in confidence as they lofted the ball and nailed points to widen the gap and seal the victory.
The second Test is in Wellington on Thursday.