Leeds:Australia's prepararations for the second and final Test against Pakistan here at Headingley suffered a setback when Marcus North missed Monday's training session at Yorkshire's headquarters.
North, the bowling hero of Australia's 150-run series opening win at Lord's last week, where the occasional off-spinner took a Test best six for 55, was ruled out of practice because of stomach illness.
Meanwhile seamer Ben Hilfenhaus did not bowl during Monday's session after suffering a shoulder injury sustained falling awkwardly in the field at Lord's.
But with two days to go until Wednesday's start, Australia remain confident of naming an unchanged side.
If replacements are needed, the uncapped duo of batsman Usman Khawaja and seamer Peter George are both in the tour squad.
North has already missed one Test through illness, against South Africa in Cape Town last year, when a stomach bug allowed leg-spinner Bryce McGain to make his debut.
Australia have added Clint McKay, who remained in England after the recent one-day series to play Twenty20 cricket for Yorkshire, to their Test squad as cover for Hilfenhaus.
But Australia physiotherapist Alex Kountouris is still working with Hilfenhaus and Australia vice-captain Michael Clarke told reporters at Headingley on Monday: "I don't think he bowled today, he's still seeing the physio but he's certainly improving.
"Fingers crossed, hopefully he'll be right come day one of the Test match.
"He's had a few niggles over the last couple of years of his career. He'll be disappointed if he misses the Test match but he's in good hands with Alex, he knows what's going on and has spent a lot of time with Hilfy over the last year or so. I think he'll get him on the park.
"If he misses out it gives someone else an opportunity."
Australia have already seen two players make their debut on this tour already, with both wicketkeeper Tim Paine and leg-spinner Steven Smith playing their first Test at Lord's.