The Wallabies midfielder Matt Giteau is back training, but loose forward David Pockock and fullback Israel Folau are still recovering before their World Cup quarter-final against Scotland at Twickenham on Monday morning.
Giteau hurt his ribs in last weekend's victory over Wales, while Pocock injured his calf and fullback Folau aggravated an ankle problem.
Pocock's ability to turn over the ball at the ruck has made him one of the most valuable players at the tournament, though Cheika does have another world-class openside flanker available in Michael Hooper, who returns from a one-match ban.
Folau, who first rolled his ankle against England two weeks ago, has been Australia's most potent attacking weapon for the past two years and would probably be replaced by Kurtley Beale if he was unable to face the Scots.
Giteau, however, looks set to recover in time to take his place in the side at inside centre and win his 100th cap.
"Giteau didn't train yesterday but is okay to train today," Cheika said. "The other two we read as we go."
Cheika has been relatively fortunate with injuries in the campaign so far, losing only lock Will Skelton and number eight Wycliff Palu from the squad permanently despite physical pool matches against Fiji, England and Wales.