The New Zealand netballers have lost 46-40 to Australia in their third and final test in Auckland.
The result is a big turn-around for the visitors, who lost 59-40 to the Silver Ferns in Wellignton earlier this week.
Australia pulled out to a five goal lead by the end of the first quarter, but the Silver Ferns managed to bring it back to 22-all at half-time.
The two teams were goal-for-goal in the third quarter, and with the scores locked at 31-all, it looked set to be an exciting finish.
But the Silver Ferns were no match for the Diamonds' defence in the final quarter, and despite a few changes in the mid-court and shooting circle during the last fifteen minutes, New Zealand only scored 9 goals to Australia's 15.
The 46-40 victory gives the Diamond's the series win and the new Constellation Cup, which will be contested by the two sides every year.
The two teams won't meet again until the Commonwealth Games in Delhi next month, where they're likely to meet in the final.