Scotland captain Bryan Redpath could be out of action for 12 weeks even though he did not break his elbow during the defeat by South Africa as had been feared.
The Sale Sharks scrum-half sustained a tear to the bicep muscle in his left arm and was rushed to hospital during the 28-19 loss at Ellis Park.
Redpath will now see a consultant orthopaedic surgeon back in Britain on Tuesday for a full assessment with coach Ian McGeechan hopeful he will return to training in six weeks.
Lock Nathan Hines suffered a severe joint disruption on his right side and is expected to be out for the same time as Redpath.
Both men could now miss the World Cup warm-up games against Italy, Wales and Ireland in August and September but are expected to be available for the finals themselves.
