Australia have been handed a big setback ahead of the highly anticipated Ashes series, with captain Pat Cummins officially ruled out of the first Test in Perth due to a persistent back injury. The opening match of the five-match Test series against England is scheduled to begin on November 21, and Cummins has still not yet resumed bowling as he recovers from a back stress injury. Steve Smith will take charge of the side for the first Ashes Test.

"We've grappled with it for a little while. The nature of the injury is that you never know, and you're sort of taking it a day by day. We've run out of time. We sort of flagged this a week or so ago that it would take sort of four plus weeks to get him up and running and we've run out of time, unfortunately, but really optimistic and hopeful for the second Test match," head coach Andrew McDonald told reporters in Canberra.

"So I suppose the next question is what's the time frame? What does it look like for the second Test? Not really going to be able to answer that other than to say that he'll be back bowling this week and that's a huge step. That was the big variable that we wanted to add in and get that information. So we're on the journey to that second Test and very hopeful that that will be a positive outcome."

Injury to Pat Cummins could open the door for Scott Boland as a likely replacement.

"Losing your captain's not ideal, but when you talk about Scott Boland being the potential replacement, it's not a bad position to be in. Ideally we want the captain available for stability and decision making but...Steve Smith will slide into that position.

"I suppose you get excited about when he does come back, what an injection that will be to the group, a fully fit Pat Cummins returning some stage during the Ashes and that's what we're hopeful for."