Rangers defender Andy Webster may need to have another operation on his troublesome knee.
The Scotland international has been bothered by the problem since January and Walter Smith is worried that more surgery may be required.
"There is a little bit of cartilage causing him a problem and he may need to go back in and get it tidied up.
"He has not had the best of luck because, although it's a straightforward procedure, you are looking at another four or five weeks before he is back again."
Surgery for Smith
Steven Smith is also likely to go back under the knife for the pelvic injury that has kept him out since last December.
"It might be he will need another operation because it has been causing him a bit of bother," said Smith.
"The frustrating thing is he has done all his rehab fine. It's just in games when he kicks a ball that he is getting a problem."
Meanwhile, Smith has refused to blame Rangers' shock 2-1 defeat to Dundee United on the fact that it came just days after the UEFA Champions League draw with Barcelona.
He said: "The European game had nothing to do with it. The players were not tired and we saw that in the second half.
"It was disappointing to lose a game that we put a lot into."