Shane Watson is in doubt for the third Test against Sri Lanka after suffering a calf injury at the MCG on Boxing Day.
All-rounder Watson has played a key role in establishing Australia's dominant position in the second Test in Melbourne, with his first-innings knock of 83 the second highest in the game so far, behind only captain Michael Clarke (106).
Australia reached 8-440 by stumps on day two, leading Sri Lanka by 284 runs.
"Shane sustained a left calf injury while bowling on day one," Cricket Australia physiotherapist Alex Kountouris said in a statement on Thursday night.
"He was able to get though the batting innings today and is likely to field on day three.
"Whether he bowls in the second innings will be determined closer to the bowling innings.
A decision on whether Watson plays in the third Test, starting January 3 at the SCG, will be made at the end of the Melbourne Test.
Rob Quiney replaced Watson for the first two Tests against South Africa at number three earlier this summer when a calf strain kept him out of the team.
Watson also missed the whole of the last Test summer with hamstring and then calf problems.