Australia paceman Mitchell Starc is in doubt for the return Ashes series against England after suffering a stress fracture in his lower back.
The 23-year-old left-armer flew home from England after Australia lost the Ashes 3-0 and scans had shown an "early stage" fracture, Cricket Australia (CA) said on Monday.
"His management plan will be determined in the coming days but he is expected to be unavailable for a prolonged period," CA chief medical officer Justin Paoloni said in a statement.
Australia's emerging crop of fast bowlers have all suffered lower back problems, with James Pattinson forced to leave the Ashes tour after two tests and 20-year-old talent Pat Cummins already ruled out for the return five-match series.
Three-test seamer Jackson Bird, who also returned home with a back injury, was expected to be fit for the Ashes, CA said.
Paceman Ryan Harris, Australia's top wicket-taker in the recent Ashes series, will be sidelined for two months with a hamstring problem but should be ready for the first test against England starting Nov. 21 at the Gabba in Brisbane.