Brad Hogg's flu-like symptoms caused the veteran to skip Friday's main training session as Australia sweat on the fitness of the wrist-spinner for Saturday night's World Twenty20 clash with West Indies.
Following Australia's comfortable win in their opening Group B game against Ireland on Wednesday, George Bailey's side had appeared settled with Hogg complementing a three-pronged pace attack of Mitchell Starc, Pat Cummins and Shane Watson.
However illness has swept through the camp with Starc unable to train on Thursday because of gastro, although the left-arm quick was back bowling in the nets on Friday at Colombo's Colts ground.
So too was left-arm finger-spinner Xavier Doherty, who's in line for a recall should Hogg fail to prove his fitness.
Another option for selectors would be bringing the game's most successful batsman David Hussey back into the line-up, with Hussey's offspin another string to his bow.
Clint McKay, who bowled well in Australia's two warm-up games against New Zealand and England, is a strong contender if Starc doesn't play.
A team spokesman said Hogg's condition is improving and Bailey is hopeful of having the 41-year-old available to play against the Windies.
Bailey has given his pace bowlers a licence to pitch short against Caribbean master blaster Chris Gayle as the Aussies aim to capitalise on what's expected to be a bouncy pitch at Colombo's Premadasa Stadium.
Watson and Starc claimed five victims between them against Ireland, including Watson's breakthrough with a bouncer from the first ball of the match.
"If we can target their helmets a little bit maybe that's a way we can force them to change their plans," Bailey said on Friday.
Gayle, Dwayne Bravo and Kieron Pollard are three of the Windies' big hitters for whom Bailey is making grand plans.
"They are good strikers of the ball and the dimensions of the ground and our pace bowlers means one of the keys for our game plan will be making them hit balls into areas they don't like," Bailey said.
"Most of their strikers like to hit the ball down the ground. They like to target mid-on and mid-wicket so if we can force them to hit into different areas that might change up their game plan.
"It's a good sized cricket ground. Strong batters can still clear the ropes but miss-hits are generally being caught on the fence.
"Watto's tone the other day really set us up. His bouncers were right on the money and it was probably as quick as he's bowled in a while too.
"We were aggressive with our body language, aggressive with our bowling and the way Davey Warner and Watto (60-run partnership) started our batting innings was aggressive."