Australia believe their first netball series victory over New Zealand since 2011 will give them a mental edge heading into next year's Glasgow Commonwealth Games.
Australia took an unbeatable 3-1 lead over the Silver Ferns in the Constellation Cup, with a 52-47 win in Melbourne on Monday night.
The fifth and final test is in Canberra on Sunday.
Diamonds coach Lisa Alexander has backed a youthful line-up in the past three tests but has yet to decide whether to experiment with in the final test, saying winning the series 4-1 would give them a major boost in the lead-up to the Glasgow Games.
The Silver Ferns have beaten Australia in the past two Commonwealth Games finals, including a double extra-time thriller three years ago in New Delhi.