Surrey and England pace bowler Chris Tremlett has had an operation on his back, it has been confirmed.
Tremlett had the procedure at a London hospital on Wednesday after being forced to return home early from England's series against Pakistan.
The fast bowler flew home before the second Test when a scan revealed a bulging disc in his back.
Tremlett has played once since being ruled out of last summer's Test against India at Trent Bridge.
The player's rehabilitation programme will be closely supervised by the England medical team in conjunction with Surrey and a date for his return to cricket will be agreed in due course.
The 6ft 7in fast bowler took 17 wickets in three Tests in England's 2010/11 Ashes victory in Australia but has only played once since the injury forced him to miss the Trent Bridge Test against India.