Wigan Athletic boss Roberto Martinez has major concerns for James McCarthy over his ankle injury.
The 19-year-old was left writhing in agony following Fabrice Muamba's challenge midway through the first half of their draw with Bolton Wanderers and received lengthy treatment on the pitch before leaving on a stretcher.
McCarthy, who has played in all Wigan's Premier League games this season, was then taken to hospital, and player and manager must now wait for the results of an X-ray that will determine how long he will spend on the sidelines.
Martinez said: "He's gone to the hospital and we'll get the results over the next 24 hours but it doesn't look too good.
"It's a real shame because he's a very young man but he's very mature on the pitch and he's been performing in a very special manner."