Australia v Sri Lanka, 1st Test, Hobart, 4th day December 17, 2012

Watson likely to lead on Boxing Day

Shane Watson's Australian Test captaincy debut on Boxing Day is now a "distinct possibility" following Michael Clarke's suffering of a hamstring strain in the first Test against Sri Lanka, according to the national coach Mickey Arthur.

While Clarke led his team in the field on the fourth day and after scans and treatment overnight will do so again on the fifth, his barely mobile state was plainly clear, leaving him in considerable doubt to be fit in time for the biggest date on the Australian cricket calendar. Arthur confirmed this, and mentioned the former wicketkeeper Brad Haddin among a quartet of batsmen in the queue to replace Clarke.

"It is a distinct possibility, it would be a really good challenge for Shane," Arthur said. "We'll learn a lot about Shane and his leadership ability, I'm confident he will come through it very well. If it does materialise, it will be a really good opportunity for him.

"That batter, whoever it is, would have to be part of our extended squad. There are possibilities. [Brad] Haddin's one of them, [Rob] Quiney's one of them and certainly Usman Khawaja's very much in the frame. Alex Doolan has played well also."

Arthur said Clarke was resolved to stay out in the field so long as the Test needed to be won, and having taken two wickets on the fourth evening Australia look in fair shape to take a 1-0 series lead on the final day.

"He will get all the treatment he needs, he will get that after hours tonight and he will get that tomorrow between breaks," Arthur said. "You would have to cut Michael's leg off for him not to be out there. He certainly wants to marshal the troops and he wants to be there if hopefully sometime we can clinch a win. We don't know exactly the extent of the injury just yet. We will wait for the scan and once we have the scan we will be able to assess."

Arthur also confirmed that Ben Hilfenhaus' side injury was serious enough to rule him out of the Boxing Day Test and in all probability the New Year's Test in Sydney. He nominated Jackson Bird and Nathan Coulter-Nile as the two men most likely to join the squad in Melbourne, as Australia's list of injured fast bowlers has now extended to seven.

"All I can say is we've had a list of bowlers leading into our summer, and we're well down the list at the moment," Arthur said. "But it's going to be a fantastic opportunity for a couple of those guys. The names that have been on everyone's lips are guys like Jackson Bird, it could be Nathan Coulter-Nile, and that will form part of the discussions we have tonight."

Daniel Brettig is an assistant editor at ESPNcricinfo. He tweets here