Melbourne - Australian captain Michael Clarke batted in the nets on Monday and voiced confidence he would play the Boxing Day Test, although selectors said he would only pad up if fully fit.
The world's leading Test batsman suffered a hamstring twinge in the 137-run win over Sri Lanka in Hobart last week and has been undergoing intensive physio ahead of the second Test at the Melbourne Cricket Ground.
"I love playing at the MCG in the biggest Test of the year but I have never done it justice," Clarke said in a column for the Sydney Daily Telegraph.
"I'm still searching for my first hundred there and will be doing everything in my power to make sure it comes this week.
"That has included working overtime with our team physiotherapist Alex Kountouris to make sure my hamstring is right for Boxing Day.
"I only suffered a minor twinge while batting in Hobart and remain confident that I will be fine to play," he added.
In the nets, Clarke faced throw-downs from assistant coach Stuart Law Monday under the watchful eye of coach and selector Mickey Arthur.
He then took a break before emerging again to bat for about 20 minutes against bowlers including left-arm quick Mitchell Johnson.
However, chairperson of selectors John Inverarity rated the skipper only a 50-50 chance of being passed fit.
"He's a very precious asset and I would go low risk," Inverarity told reporters late Sunday of Clarke, who has reclaimed the top spot in the latest ICC Test batsman rankings.
"He's always upbeat, he desperately wants to play.
"But we certainly don't want to push him especially hard in a Test and for him to break down."
Clarke has had an extraordinary season, scoring 1 489 runs at 106.35 and is just 55 runs adrift of Ricky Ponting's Australian record of 1 544 in a calendar year ahead of the Boxing Day clash.
If he misses the game, his spot in the batting lineup would go to Usman Khawaja, with Shane Watson assuming the captaincy.
Australia lead Sri Lanka 1-0 and Clarke is keen to wrap up the three-Test series in Melbourne.
"This is a great opportunity to claim the series after our hard fought win in Hobart and go to Sydney next week in an unassailable position," he said.