Hampshire have confirmed that Jackson Bird's shoulder injury "is worse than first feared".
The complaint has kept the bowler out of Hampshire's opening three County Championship matches of the new season.
With no comeback date in sight, the club have now revealed that the 28-year-old has returned to his native Australia for treatment.
"Hampshire Cricket can confirm Jackson Bird will return to Australia after recent scans showed his shoulder injury is worse than first feared," read a statement on the club's official website.
"The amount of time that he is expected to be out of action for is not yet known, but the club are hopeful Bird could return to the Ageas Bowl later on in the season."
Hants are now in discussions to bring West Indian seamer Fidel Edwards to the club earlier than originally anticipated.