St Mirren manager Danny Lennon has confirmed Paul McGowan is likely to be sidelined for three months.
The attacking midfielder is expected to undergo surgery on a shoulder problem that will keep him out of action for the rest of the year.
Lennon told the club's website: "It isn't looking good for Paul as we wait on a report on exactly what needs to be done, but it looks as if an operation will be required."
He added: "His shoulder has been bothering him for a wee while and he got a dunt on it in the cup tie against Hamilton which flared it up, so it has got to the point that he can't go on with it as it is.
"We are waiting on confirmation on when it can be done, which should hopefully be later this week or the beginning of next week.
"It looks as if Paul will be out of action for 10 to 12 weeks.
"Losing a quality player like Paul for that length of time is a hard loss for us but we have assembled a good squad, and I certainly believe that within that squad somebody will step forward and take up the opportunity.
"It will be interesting to see how we handle the three months without Paul - but we will."