Andrew McDonald says half of Australia's T20 World Cup squad is already locked in with the looming series in New Zealand going a long way to picking the remainder of the playing group.
And McDonald has backed in under-fire captain Aaron Finch to silence the doubters this year and return to form after a woeful Big Bash League campaign.
The Australian squad is quarantining in Christchurch before starting a five-match tour of New Zealand on February 22.
McDonald is deputising for coach Justin Langer in Aotearoa as the tour was scheduled to clash with an aborted Test tour to South Africa.
The decision not to rejig the T20 side leaves established stars David Warner, Steve Smith and Pat Cummins at home, and gives opportunities to players that impressed in the BBL.
McDonald said it was now or never for those on the fringe.
"With a few of the potentially or perceived starting 11 players not being here, it creates a great opportunity for those players," he said.
"Coming off a two month BBL campaign ... straight into a five match series against New Zealand in the same format.
"If they're ever going to be ready, it's now."
Previous World Cup squads have had 15 players and McDonald said selectors already "probably got seven or eight spots locked away".
"It's really as simple as ... fitting the other players potentially in and around that."
With five matches against the Black Caps, McDonald said the order and the XI would be shuffled so selectors could learn more about the playing group.
In game one, Josh Phillippe is likely to make his international debut as one of the top three, alongside Finch and Matthew Wade, Australia's wicketkeeper in NZ.
Warner's return for the World Cup in India creates a top-order squeeze for Phillippe, so McDonald said the BBL player of the year might be tested in the middle order in NZ.
McDonald said the middle order and the make-up of the bowling attack were the biggest questions.
"We've played two spinners and three quicks across the journey ... but is that the formation to win a World Cup?" he said.
"Do we need to learn to play another way as well at times?
"Does that look like potentially an allrounder that's a bit like the 50-over team?
"We've got a few things on the table."
Finch, who has played at the past two T20 World Cups, finished the BBL with nine scores of less than 20 but McDonald said the "quality player" would bounce back.
"He's had one bad BBL campaign, which is rare. He's been stability for the Renegades over a decade. He will return to the player we know he can be," he said.
McDonald said Mitch Marsh will be nursed back into bowling action after a side strain.
"He's not ready to go flat out yet. Hopefully over the next couple of weeks that we can build him up," McDonald said.