Australia captain Pat Cummins will miss the Ashes series opener against England next month in Perth.
Cricket Australia on Monday said Cummins has resumed running after being sidelined for three months with a back stress injury but "will not be fit in time for the opening match".
It added that Cummins "expects to return to bowling shortly".
Former skipper Steve Smith will lead Australia in Cummins' absence when the biggest test series on the 2025 calendar starts on November 21, followed by a day-night test in Brisbane from December 4. The five-match series then moves to Adelaide, Melbourne and Sydney.
The 32-year-old Cummins hasn't bowled since Australia's 3-0 series sweep of the West Indies in the Caribbean in July.
His absence means Scott Boland is likely to join Mitchell Starc and Josh Hazlewood in Australia's pace attack in Perth, where conditions usually favour pace bowling.
In nine home tests, Boland has taken 49 wickets at an average of 12.63 — including his debut in 2021 when he snared six wickets for seven runs in a second-innings burst that secured a huge win for Australia at the Melbourne Cricket Ground.
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