South Africa all-rounder Vernon Philander will miss Sussex's One Day Cup group stage fixtures after suffering a groin injury.
Philander is signed to the English county for the first half of the 2017 season, but the injury will keep him on the sidelines for a significant length of time.
Sussex had planned for Philander to play in six County Championship matches and the group stage of the One-Day Cup, which runs from April 27 to May 17.
The 31-year-old, who has featured in 43 Tests and 30 one day Internationals for the Proteas, sustained the injury during Sussex's opening County Championship match against Kent at the weekend and will return home to South Africa for his rehabilitation.
"Sussex regret to announce that overseas player Vernon Philander will be out of action for a period of two to three weeks," a club statement read.
"We are pleased that he will return to Hove to be available for the remaining four County Championship matches of his agreed contract with the club, beginning with the match against Durham on Sunday, May 21, finishing in the middle of June.
"He will now however be unavailable for Sussex's Royal London One-Day Cup campaign."