Rangers winger David Templeton will be sidelined for up to five weeks with ankle ligament damage.
The former Hearts player was stretchered off with a suspected broken ankle
during last weekend's goalless draw at Annan.
Rangers boss Ally McCoist said Templeton had suffered major swelling and damage to the ligaments.
signed a four-year deal
with the Ibrox club at the end of August.
McCoist said it was a blow for the Third Division outfit to lose Templeton.
- Began senior career with Stenhousemuir in 2005 and went on to score 11 goals in 36 appearances
- Joined Hearts in 2007 and was sent on loan to Raith Rovers the following year
- Netted four times in 17 Raith appearances
- Became Hearts regular in season 2009-10 and was nominated for PFA Scotland player of the year in 2010-11
- Leaves Hearts having made 95 apperances and scored 13 goals for Tynecastle club
"David has obviously got a very sore one," said McCoist. "The good news is that it's not broken.
"He has been for an X-ray but there is massive swelling and there looks to be a good bit of damage to the ligaments unfortunately.
"We are waiting on the swelling going down and then David will get a scan in the next few days."
Templeton began his career at Stenhousemuir before spending five-and-a-half years at Tyncecastle.
Hearts defended the sale of Templeton to Rangers, stating that the player was desperate to leave.
"In January he could sign a pre-contract and walk for free in summer," the Edinburgh club said.
The winger scored on his final appearance for Hearts, the 1-1 draw against Liverpool in Anfield.
Meanwhile, McCoist said his side's indifferent away form was not "a disaster" despite failing to register a league victory on the road.
Rangers boast a 100% home record - but sit fourth in the table - and McCoist said he was under no illusions as to the expectations of the fans.
"We all know the pressures on getting results at this football club," he added.
"It doesn't matter which league you're in, you're expected to win games.
"The flip side of the coin is that we've had three draws away from home, which isn't a disaster.
"I do accept we should be playing better with the ball away from home and, hopefully, turning those draws into victories.
"I'm certain that the results away from home will come but it's not going to be an overnight fix."