After losing 49-48 in Perth on Sunday, the Diamonds replied with a forceful final quarter on the back of a big defensive effort and the exploits of captain Catherine Cox.
With the teams level-pegging at three-quarter time, the Diamonds stepped up to another level in the final quarter. Defender Laura Geitz and shooter Natalie Medhurst saved their best until last while Cox remained a vital cog throughout.
The Silver Ferns could not break their two-year drought of achieving back-to-back wins against Australia and head to Melbourne with a winner-takes-all contest lined up in the Constellation Cup decider.
Shooter Cathrine Latu capped a long wait in the wings because of international eligibility rules to make her first start against Australia for the Silver Ferns, ahead of stalwart Irene van Dyk, in an otherwise unchanged line-up to the previous test.
Despite a shaky first outing, the Diamonds stuck with Cox under the hoop while Erin Bell got a start at wing attack and the towering figure of Susan Fuhrmann got the nod at goalkeeper.
The Silver Ferns got away to a flyer, racing out to a 5-1 advantage before the Diamonds overcame a stuttering start to reel the New Zealanders in. Once Latu settled, her subtle movement and balance came to the fore as she out-witted Fuhrmann to garner perfect shooting positions.
Cox was back to her best at the other end, erasing memories of her 65 percent return from Sunday's test with a clinical 11 from 11 shots in the first quarter. In a tight opening quarter, it was the Silver Ferns who gained the slightest of advantages to head into the first break with a 14-12 lead.
Unable to contain Latu's slick movement, Fuhrmann was replaced in the second quarter by Geitz as both teams battled to obtain any ascendancy.
The midcourt was fiercely contested, the Silver Ferns not enjoying the freedom of space and movement of the previous test. Captain Laura Langman, playing in her 80th consecutive test since making her debut in 2005, was an influential figure, showing strong driving play while picking off vital intercepts on defence.
Both teams played a mixture of good and bad, each having their moments of superiority before the other bounced back. A five-goal unanswered streak on the back of an ever-comfortable Latu and the assistance of her fellow hard-working shooter Maria Tutaia helped the Silver Ferns maintain the slightest of edges when they led 26-25 at the main break.
Kayla Cullen replaced Anna Scarlett at goal defence for a torrid and willing third stanza where no quarter was given, each pass proving a challenging exercise. Both teams again exhibited patchy passages, struggling at times to find their shooters as the defensive pressure lifted.
Geitz and Julie Corletto picked off crucial intercept ball as the Silver Ferns looked to steal a march, Australia not backing off as Cox and Medhurst hauled their team back on to level terms at 36-all going into the last break.
Scarlett replaced Leana de Bruin at goalkeeper for the final quarter but the Silver Ferns could not contain a rampant Australia in the run home.