Sean O'Brien and Jared Payne have both emerged as doubts for Ireland clash with Australia.
Both players sat out the captain's run on Friday but they haven't been ruled out of the week-end's match.
Assistant Ireland coach, Andy Farrell, says both players are carrying 'lower limb tweaks' and that they will undergo fitness tests ahead of the game. O'Brien admitted on Thursday that he was still 'a little bit off' and that he had yet to return to full fitness following the serious hamstring injury which he suffered last February.
Munster's Peter O'Mahony and Rory Scannell have remained with the Ireland squad as injury cover.
Meanwhile Rob Kearney and CJ Stander have both come through their return-to-play protocols and are fit to start as selected.
