Australia remain unbeaten after two pool matches, although their performances have left key selection decisions in focus before the knockout rounds.
Reece Walsh is set to start at fullback against the Cook Islands, ahead of James Tedesco, after Isaah Yeo suggested the team was settling on its strongest line-up.
Walsh played fullback in Australia's 24-22 opening win over New Zealand. Kevin Walters then made several changes for the Fiji match, selecting Tedesco at fullback and leaving Latrell Mitchell out at centre.
Tedesco performed well, but Australia had to withstand a determined Fiji side to win 36-22.
"This team (against Cook Islands) is something we feel like we can take forward and continue to grow," Yeo said when asked about the players who could play in the spine.
"It is a real blessing this Australia has so much depth and that gives players opportunities but once you approach the knockout (rounds) you want to be settled."
Yeo's remarks also raise questions about the centre positions. Bradman Best and Kotoni Staggs have been picked against the Cook Islands, potentially leaving Mitchell out again, with Best possibly preferred on the left edge.
Yeo said Australia wanted to build confidence before the knockout stage. "We just want to walk off the field on Saturday night happy with the performance," he said.
"I feel like we have in some parts in the first two games. You want to be taking steps forward and getting confidence from your performances and we are going to need that going into knockout footy."