Australia are still sweating on the injuries of back-row David Pocock, full-back Israel Folau and prop Scott Sio after the trio failed to complete training on Wednesday.
Pocock (calf) and Folau (ankle) missed the Wallabies' 35-34 quarter-final victory over Scotland and Sio left the field during that match with an elbow injury.
According to the Sydney Morning Herald, all three are still doubtful to face Argentina in Sunday's semi-final at Twickenham.
Pocock spent Wednesday's entire training session on a stationary bike, Folau only got through 10 minutes before coming off to ice his ankle and Sio took part in light training before jumping into an ice bath.
Sio is viewed as the most unlikely to play against Argentina but there's great concern in the Wallaby camp that Pocock and Folau will also be unable to play.
Wallabies head coach Michael Cheika will give all three players until Saturday to pass fitness tests before naming his matchday 23.
Kurtley Beale is favoured to wear the number 15 jersey again after impressing as Folau's replacement against Scotland. Cheika praised Beale for his performance in the quarter-final.
"I thought Kurtley Beale was outstanding at fullback," said the coach.
"Even the decision he made at the end, when we got the ball back, and he kicked it long into the corner there – that's not a decision he would've made a couple of years ago.
"He thought about what the team strategy could be there, put a great kick in there and gave us some field position to try and put some pressure on the opponent. He considered the conditions and everything like that.
"I thought he had a great game."
Ben McCalman is set to start at number eight again if Pocock is ruled out while James Slipper is favoured to replace Sio at loosehead prop.