Rangers striker Steven Thompson is likely to be out of action for six months with knee ligament damage.
Steven Thompson faces a season on the sidelines
The Scotland international saw a specialist last week after aggravating an injury in the victory over Dunfermline at Ibrox on 13 September.
And the former Dundee United forward will undergo an operation on Friday that is almost certain to require reconstructive surgery and a long period of recovery.
"Hopefully, the lay-off will be nearer three months than six," Thompson told BBC Sport. "It all depends on how I react to the operation.
"The medical team at Ibrox is first class and I'm sure they'll give me all the support I need to make as swift a recovery as possible.
"The specialist told me it would be anywhere between three and six months, so I'm aiming to be back after three months and one day."
Thompson, 24, originally sustained the injury in the pre-season friendly defeat against Everton after a tackle from David Unsworth connected directly with his right knee.
Thompson had made a successful return to the Rangers first team and started Scotland's recent Euro 2004 qualifying tie in Germany.
Scotland boss Berti Vogts must do without Thompson for the crucial tie with Lithuania on 11 October and any possible play-off matches, but will be pleased that Kenny Miller has returned to first team action for Wolves after a summer hernia operation.
"It's a blow because he has been playing well," said Rangers manager Alex McLeish.
"He has cemented his place in the squad and I'm really sorry that he is missing when his form was really good."