Joe Ledley looks set to miss Celtic's Clydesdale Bank Premier League clash at Kilmarnock on Wednesday and possibly the Old Firm derby.
The Wales midfielder limped off with a hamstring injury in the 69th minute of Celtic's 4-0 Scottish Cup semi-final win over Aberdeen on Sunday.
He has all but ruled himself out of the Rugby Park contest and fears he may miss the trip to Ibrox on Sunday.
Ledley said: "I will have a scan and see what that says but I don't think I will be involved at Kilmarnock on Wednesday.
"I played a pass and it sort of tightened up a bit.
"I hope I can be fit for Sunday but we will just have to wait and see what the scan says."