Scotland will be without centre Joe Ansbro for their Six Nations opener with England.
The London Irish man has been plagued by a persistent back injury recently.
Ansbro has been released back to the Aviva Premiership side ahead of the Six Nations opener this weekend.
"Joe came into our camp in St Andrews last week affected by a back injury which will need a longer period of rehabilitation," Scotland physiotherapist Paul McGinley said.
"This will be undertaken at his club and he will be re-assessed following the England game."
England face Scotland at Murrayfield on Saturday.