Australia suffered a huge setback ahead of the Ashes series next month as captain Pat Cummins was ruled out of the first Test against England in Perth.
Head coach Andrew McDonald said Cummins had “run out of time” as he recovers from a lower back injury. Veteran batter and former captain Steve Smith will lead the side in his absence.
Cummins has resumed running and should start bowling this week. There is an outside chance the 32-year-old will be fit to take part in the day-night second Test that takes place in Brisbane from December 4.
“We've grappled with it for a little while, and the nature of the injury is that you grapple with it day by day,” McDonald said.
“We're really optimistic and hopeful for the second Test match. He'll be back bowling this week, that's a huge step.”
The star all-rounder has not played since picking up a lower back injury in a Test match against the West Indies in July.
McDonald said Australia were “incredibly fortunate” to call on the experienced Smith.

In Cummins' absence, seamer Scott Boland will team up with veteran quicks Mitchell Starc and Josh Hazlewood. That is still one of the most potent attacks in Test cricket. However, Cummins' leadership and match-winning efforts at crucial moments will be a huge loss.
“Losing your captain is not ideal, but when you're talking about Scott Boland as a potential replacement, it's not a bad position to be in,” McDonald said.
Boland has quietly emerged as one of the most impactful Australian bowlers over the past few seasons despite limited opportunities.
Boland, 36, has been extremely effective on Australian pitches, taking 49 of his 62 wickets in just nine home Tests at an average of 12.
What has helped Boland is the additional help offered by lively Australian surfaces and the new batch of Kookaburra balls that offer greater assistance for longer periods. Batting averages have plummeted in Australian conditions over the past decade, from over 40 in 2015 to less than 25 last season.
Cummins, however, offers more than just wickets. The Aussies have held the Ashes urn for close to a decade and Cummins has been a leading wicket-taker in three of the four series.
In last year's Border-Gavaskar series at home against India, Cummins came up with a stunning all-round effort – 90 runs and six wickets – in the series-defining fourth Test in Melbourne to clinch an unexpected victory, take a decisive series lead and win the one trophy that had remained out of their possession for many years.
If Cummins is not fit by the second day-night Test, it will be advantage England.
If Ben Stokes can keep his team fully fit for the first two games, England can dictate terms in helpful conditions, especially with the pink ball, as they have far greater depth in bowling.
Jofra Archer, Mark Wood, Brydon Carse, Gus Atkinson and Josh Tongue, along with whatever Stokes can manage with his injury-ravaged body, will provide greater impact for a longer duration than Australia.
England also have a far more settled batting line-up than Australia, even though the hosts have more experience.
The lack of clarity around Australia's batting is such that McDonald said the selectors will consider a Test recall for Mitch Marsh, even though Australia's white-ball captain said last week he will only be watching the Ashes series on TV.
“We would be comfortable picking someone, and if you want to put a name to it, Mitch Marsh, out of white-ball cricket if we felt like that was going to benefit the Test team,” he said.
“We feel he's batting as well as he has for a long period of time. And we still haven't given up on Mitch Marsh's Test career.”
