The Ireland international was taken to hospital after falling awkwardly early in the second half.
"Marc will be out for a while, but we are not sure at this stage for how long," manager Tony Pulis told the club's website on Sunday.
The Ireland international was taken to hospital after falling awkwardly early in the second half.
"Marc will be out for a while, but we are not sure at this stage for how long," manager Tony Pulis told the club's website on Sunday.

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