The Terenure clubman has been used a replacement in Ireland's last three games against England and New Zealand (2).
Shane Horgan, Brian O'Driscoll, Mick O'Driscoll, Gordon D'Arcy and Denis Hickie run through a training drill in Perth.
Irish captain O'Driscoll has talked up the Australian backs, saying: "There was never a question about their back line - it is probably the best in the world at the moment.
"What you know with Australia is that they are a very, very smart team, probably the smartest in world rugby. If there is somewhere to exploit then they tend not to take too long getting around to doing it."
Brian O'Driscoll alongside Geordan Murphy and Mick O'Driscoll in training. Munster lock O'Driscoll is yet to start a Test match for Ireland but was used as a replacement in the two games against New Zealand.
The Irish players go through some stretches in Perth.
At Tuesday's press conference, Irish coach Eddie O'Sullivan admitted that his selection approach was "a bit boring" but that for the three summer tour Tests he has picked the best team available. Dempsey's inclusion at the expense of the benched Murphy is the only change for the clash with the Wallabies.
Alan Quinlan, David Wallace, Keith Gleeson, Paul O'Connell and Leo Cullen show off some fancy footwork during the session at Wesley College.
Leinster flanker Gleeson turned 30 last Saturday, but has failed to force his way into the matchday squad for the Perth Test. The Sydney-born forward's hunt for his 25th international cap will continue.
**All photos by Billy Stickland of Inpho Photography**