Glasgow Warriors back row forward Ryan Wilson will be out of action for up to six months with a shoulder injury.
Wilson sustained the injury playing for Scotland against South Africa last month and has undergone an operation at Spire Murrayfield Hospital.
Ryan Wilson said: "I'm disappointed to miss the start of the season but now I've had the operation I'm looking forward to beginning a period of rehabilitation, in order to get back playing as quickly as possible."
Glasgow Warriors head coach Gregor Townsend added: "This is a setback for Ryan after a very good season for club and country, but we wish him all the best in his recovery.
"I'm expecting him to play an important role for us off the field in the early part of the season and we look forward to him playing even better when he's back fully fit."