Scott Boland has been sent for a scan after a painful bowling mishap, having tumbled on the SCG pitch.
Boland stumbled while delivering the final ball of the second session on day three of the fourth Ashes Test.
The Victorian, who enjoyed a dream man-of-the-match debut at the MCG, was in much discomfort after the incident.
The fast bowler grabbed his side after hitting the deck as teammates and England batter Jonny Bairstow checked on his welfare.
Boland was spotted leaving the ground soon after.
Cricket Australia has confirmed Boland has been taken for a scan.
Earlier, Boland claimed the prized scalp of Joe Root to extend a remarkable start to his Test career.
Boland had figures of 2-0 from four overs at lunch in Sydney, while he snared second-innings figures of 6-7 to help Australia retain the urn with victory in the Boxing Day Test.
