Matthew Etherington is suffering from a torn hamstring, it has been confirmed.
The Stoke winger had to be stretchered off during their clash with Wolves on Tuesday.
The Potters went on to win 3-0 but the chances of the winger returning to duty in time for the May 14 final against Manchester City now appear slim.
Assistant manager Dave Kemp said: “The scan has shown there is a tear on the hamstring, so that’s not the best news. But we are doing everything we can to get him ready for the final.
“Initially we have iced down the injury, but then we can use oxygen chambers and every remedy we possibly can to shorten the recovery time.”
“It would be a massive disappointment if Matty misses the final, but we will know more when he has had the scan,” Tony Pulis said earlier in the week. “We haven’t got the resources that Manchester City have and it would be hard enough for us to take them on with all our top players fit, but now we have a major doubt on top of the fact that we have already lost [Ricardo Fuller] and Danny Higginbotham.”