Newcastle United defender Florian Lejeune is facing a scan to determine how much damage he has suffered to his left knee.
The Frenchman has a suspected cruciate ligament injury which will rule him out until next season, but he is facing further assessment with club doctor Paul Catterson in the next 24 hours.
Lejeune went down in a heap in the second half and gestured to be subbed immediately following a challenge with Andros Townsend.
The former Manchester City and Eibar defender was applauded off the field and replaced by Paul Dummett for the closing stages.
Toon boss Rafa Benitez was awaiting more updates on Sunday but said after the game: "He said he felt a click in his knee, so that is bad news normally."
But the injury is not on the same knee that ruled him out of the start of this campaign when he was hurt in pre-season.
Benitez said: "It seems bad. It's the other knee, but it seems bad, so we have to wait and see what the doctor says tomorrow."
United will go into the game against Leicester City at least safe in the knowledge that Federico Fernandez is fresh and ready for another chance after being an unused sub against Crystal Palace.
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