Michael Clarke, the Australian captain and selector, must weigh up the fitness of his spearhead Ryan Harris and the century at No. 3 by the debutant Shaun Marsh as he travels to Colombo with a 1-0 series lead over Sri Lanka after the second Test in Pallekele was washed out.

The Australians would have been heavily favoured to finish off the series had five full days been possible, and even another two hours on the final day might have been enough as Sri Lanka teetered with a lead of 80 and four wickets left when the rain returned for good.

Harris, who claimed six wickets for the match and has been the most dangerous bowler on either side so far, left the field after the last of his spells, complaining of hamstring stiffness. Clarke said Harris' physical well-being would be a pivotal concern in the three days between Pallekele's soggy conclusion and the start of the final match at the batsman-friendly SSC ground.

"There's always been concerns about Rhino's fitness because unfortunately he's dealt with a few injuries throughout his career," Clarke said. "He's a very strong bloke and he'll do anything to get on the park. He has a bit of hammy stiffness so tomorrow he'll have a scan just to find out if there's anything there but we're confident, if the scan shows nothing, that he'll certainly be available for the third Test. If it does show something there's going to be a little bit of doubt.

"He's been a very good bowler for a long time now, it's just obviously with Harry his body … trying to keep him fit and healthy. He's got this issue with his knee that he's dealt with for years that is going nowhere. It's part of what he has. He's a wonderful player to have in your team, not just the way he bowls, he's got plenty of talent with the bat. He's as good as any fast bowler in the world in the field. And he brings a lot to the team as a guy. He's one of those guys you want in your team.

"He's having a big impact in this series. Hopefully he's fit for game three - if he's not it gives somebody else an opportunity and it's about trying to make sure we get him as fit and healthy as we can for our next series against South Africa. We're not silly - we know with every game Rhino plays there's going to come a day that his knee can't take it anymore or his body can't take it anymore, like all fast bowlers. It's just about trying to manage him as best as we can. He's certainly been doing the business for us."

Harris may have been in line for a rest irrespective of his injury status, given the rigours of three back-to-back Test matches. Clarke said that option had been a point of discussion across the tour, with the Victorian duo of Peter Siddle and James Pattinson sitting in reserve.

"There were discussions about all the fast bowlers, having three back-to-back Test matches with big workloads on generally pretty flat wickets here. Tough bowling conditions," Clarke said. "Certainly concerns about all the fast bowlers but maybe rain has saved [Harris] from a few overs. Finishing a day early in the first Test probably saved him a bit there as well.

"He feels okay at the moment, it was more precaution. I said to him once he finished that spell that it was unlikely he was going to bowl again today so he should go off and see Alex (Kountouris, physio) and do what he needs to do to ensure we're not doing anything silly. Fingers crossed, hopefully it's clear."

Less clear is what will be done about Marsh, who would have been expected to lose his spot to Ricky Ponting before he impressed all observers with a committed 141 at No. 3. Ponting is guaranteed to return, leaving Marsh, Usman Khawaja and Phil Hughes in a fight for two remaining batting places. Clarke and the coach Tim Nielsen will be the men on the ground making the call, following the selector Greg Chappell's pre-planned departure from the tour at the outset of the second Test.

"Interesting couple of days coming up. Like I said before this Test match it's not a bad problem to have, a problem that we've been looking forward to for a while," Clarke said. "Unfortunately not all the batters can play, someone's going to have to miss out. I'll need to speak to Tim, who is obviously a selector, and the other selectors back home and we'll make that decision.

"I've got a couple of ideas in my own head at the moment but, like I say, I think it's important I communicate with the other selectors, see how they feel and then we'll go from there. The first thing is to work out what six batters we feel are the best six batters for the next Test match. Once we do that then it's obviously up to me to select the batting order. Time will tell I guess.

"I think it's important that we do have a long hard think about what six batters we're going to go with. It's obviously hard. Shaun's batted beautifully, Uzzie's done pretty well since he's come in and I thought Hughesy looked really good the other day and unfortunately didn't go on, and we've got the great Ricky Ponting coming back. It's a good problem to have."

Daniel Brettig is an assistant editor at ESPNcricinfo