Brisbane - Australia vice-captain Michael Clarke trained on Tuesday for the first time this week, telling team-mates his back injury was improving ahead of the Ashes Test opener against England.
Clarke missed last week's Sheffield Shield game for New South Wales against Tasmania as a precaution, and sat out Australia's first training session in Brisbane on Monday.
But after looking a little restricted in his movements during a slips catching session, Clarke appeared to bat without discomfort in the nets as he faced throw-downs from national coach Tim Nielsen at Tuesday's team workout.
NSW team-mate Usman Khawaja has joined the squad on standby for Clarke, and the Pakistan-born left-hander, 23, is in line to make his Test debut at the Gabba on Thursday if Clarke cannot play.
However Australian fast bowler Mitchell Johnson said Clarke is on track to play against England in the Brisbane Test.
"He batted for about 45 minutes today. He had a bit of a throw-down in the outside nets," Johnson told reporters.
"He said that he felt pretty good with the throw-downs and with the batting stuff that he did so that's good signs for him and for Australia.
"He's still got another two days to prove himself.
"To have someone like Michael not in the team would be a big loss for us. He has been doing everything he can to get right."