The Diamonds have set their sights on bringing more grit and mongrel to the court as they attempt to avoid gifting arch rivals New Zealand the Constellation Cup.

Australia are 2-0 down in the four-match series after suffering 64-50 and 63-52 losses in New Zealand.

If the Diamonds win Sunday's match at Perth's RAC Arena and follow it up with a win in Melbourne next Wednesday, extra time will be played to determine which country are crowned the Constellation Cup champions.

The Australian squad are not panicking despite the poor displays in NZ, but it remains to be seen whether coach Stacey Marinkovich will swing the axe for Sunday's must-win match.

Marinkovich already made a big statement in game two by benching captain Liz Watson after the first quarter.

Defender Rudy Ellis, who made her Diamonds debut against England last month, said the team knows what they need to do to beat NZ.

"It takes a lot of grit, a bit of mongrel in defence and just that resilience in attack," Ellis said.

"I think (the 2-0 deficit) just inspires us even more to really put absolutely everything out there.

"It's do or die. I think we work really well under pressure, so I'm really looking forward to the challenge.

"I don't think our confidence has been affected too much. We're a pretty positive bunch.

"We're just really excited to step out there again and have this challenge ahead of us."

The Diamonds are yet to find an answer to star Silver Ferns shooter Grace Nweke, who scored 50 goals in game one and 47 goals in game two.

Nweke is 193cm tall, and Diamonds defender Sunday Aryang said it was imperative to limit her supply.

"Grace does have some great form at the moment," Aryang said.

"I think for us, it's just working together in that circle, being able to get up for those balls and even slowing it down as much as possible outside of the circle.

"As long as we can shut down what's happening outside, it should bring some impact in the (circle)."

NZ last held the Constellation Cup in 2022, and Australia are determined to claim the crown for a third straight year.