Dundee United midfielder Danny Swanson may be ruled out for up to two months with a knee injury.
The 24-year-old has strained his medial ligament.
Swanson, who was signed by Craig Levein during his reign as United boss, was called up for the final Euro 2012 qualifiers against Spain and Liechtenstein.
The injury means the midfielder will miss Scotland's friendly against Cyprus next month.
Swanson's time at Tannadice has been dogged by repeated injury setbacks.
"It's such a shame for Danny because he has been in good form but there's nothing you can do," said manager Peter Houston.
"He worked very hard to get fit again and was playing so well he won a call up for Scotland.
"So it's a shame for him but he's a tough character and will be doing everything he can to get back as soon as possible."