Australia fast bowler Patrick Cummins has been ruled out for at least four months with a stress fracture in his lower back.
The 19-year-old, who took seven wickets in his only Test match against South Africa in 2011, is regarded as one of the best young pacemen in the world.
This will be the second consecutive Australian summer he has missed.
"We expect he will recover fully from this injury," said Australian team physiotherapist Alex Kountouris.
It is the second time Cummins's career has stalled because of a stress fracture in his back, although this latest injury is in a different area of the spine and has been identified in the early stages.
Australia tour England for a five-match Ashes series in July and Cummins, who has only played four first-class games in his career, may struggle to regain fitness in time to take part.
The Sydney-born bowler told Cricinfo he was booked into the Australian Institute of Sport to have his action examined before the latest injury was identified, to try and determine what is causing his fitness problems.