Australian coach Darren Lehmann expects David Warner to be fit to play next Tuesday's first Test against Sri Lanka in Kandy.
The opening batsman is racing the clock as he battles to overcome a broken finger sustained in last month's tri-series in the West Indies.
The vice-captain was only able to face slow bowlers in the nets using one hand a week ago, however Lehmann said it was now his belief Warner would be available to play in the match.
"We're preparing for him to play," Lehmann said.
"He's been batting the last couple of days and I can't see a problem.
"I haven't really spoken to the medical staff, they usually come up to me if there is some sort of issue."
Warner's inclusion is likely to mean Shaun Marsh will again be left out of the Australian XI, despite impressing early on the tour.
The only other spot of contention in the team is likely to be whether Lehmann opts to select two spinners on a turning pitch or stick with three seamers.
"We'll get to Kandy, see what the wicket is like and make a call from there."
Second-choice spinner Stephen O'Keefe impressed in the most recent tour match against a Sri Lankan XI at Colombo, taking 10 wickets for the match and top-scoring with the bat with 78 in Australia's only innings.
"He's worked really hard," Lehmann said.
"He's a lively, buzzy character for us. And played exactly the role we want him to play over here in this game."
The other advantage of playing O'Keefe will be the option of having two bowlers who spin the ball different ways.
While Lyon is a traditional offspinner, O'Keefe's left-arm orthodox tweakers spin the ball back across the right-hander.
"(He) obviously complements Nathan well spinning it the other way," Lehmann said.
"We think that's the way to go.
"Obviously India do it there with (Ravindra) Jadeja and (Ravichandran) Ashwin and most teams have spinners going both ways so for us that's important."
Australia's third seamer from their most recent Test in New Zealand, Jackson Bird, took two wickets in the Colombo tour match.