MICHAEL Clarke's hopes of playing in the Boxing Day Test have faded as Australia takes a conservative approach with its inspirational captain, while Shane Watson says stepping into his shoes would be the pinnacle of his career.
National selector John Inverarity said on Sunday that Clarke was too precious an asset to gamble with, and the hamstrung captain did not break out of a brisk jog at training.
Clarke was restricted to run-throughs with physiotherapist Alex Kountouris and walking laps with Inverarity at Sunday's MCG training session before leaving for more scans on his hamstring to check his progress.
''I've stated that I would prefer to take a conservative approach,'' Inverarity said. ''He is a very precious asset and I would go low risk, but with an outstanding sportsman like Michael, it's very hard to hold him back.
''He's always upbeat and he desperately wants to play. But we certainly don't want to push him especially hard in a Test and for him to break down.''
Leading into the last Test of 2012, Clarke is on the verge of breaking Ricky Ponting's record for the most runs by an Australian in a calendar year.
But the last time the captain bypassed medical advice to hurry back from a hamstring injury - for a one-day final against Sri Lanka in February - he ended up straining the other one, and missed an entire one-day tour of the Caribbean.
Not even Watson thought of himself as a captain until he became one, deputising for Clarke as captain of the one-day team last summer and for a series in the West Indies, but the all-rounder said he enjoyed balancing the job with the many other elements of his game.
''It's about as big as it gets for an Australian cricketer - like it was when I captained the one-dayers,'' he said.
''It's amazing to think that something like that has come along in your life. But I'm trying not to get too far in front of myself at the moment.
''In the end, I know Michael will be trying everything he can to get ready for this Test match.
''Everyone has got fingers crossed that he'll be right, but if the opportunity does arise, I'll refocus then.''
Leading Australia on Boxing Day would be a huge challenge for Watson because of his bowling workload, which peaked during the first Test in Hobart, his need to contribute more as a batsman than he has during the past two years, and the ever-present danger of injury. ''I've got a little bit on my plate,'' he said.
But Watson said that the experience of captaining the one-day team in games last season, for four wins, three losses and a tie, allowed him to focus on things other than his own performances.
''The first thing I observed is how much I loved doing it,'' he said. ''I had as much fun as I've had on a cricket ground without performing to my potential on a few of those days.
''To be in control and feel every single ball of what's going on on the ground is something I really enjoyed.
''The other thing that stood out to me was to trust my gut instinct. Until you captain a side, you don't really realise the intuition you've developed over those 10-11 years of playing first-class cricket and just being around some of the best players to have played for Australia.
''Intuition really does come to the fore and you're able to do things tactically that you didn't think you had inside of you.''
Former captain Ponting last week backed Watson to do a fine job if he had to captain Australia, as long as he didn't think too much about it.
The all-rounder has also consulted Shane Warne, his former captain at Rajasthan in the IPL, about on-field leadership.