Tom Soares is expected to be out for at least two months after possibly breaking his ankle during the 2-0 capitulation to Southampton on Tuesday.
The 20-year-old midfielder limped off at half-time of the midweek match, adding to what is becoming a midfield injury crisis for Peter Taylor with skipper Carl Fletcher and England U21 international Ben Watson already ruled out of upcoming matches.
"It doesn't look good," said Taylor. "It could be two or three months because it looks as though he might have a little crack in his ankle."
"Losing Carl, Ben and Tom has hurt us, because they can be defensive midfielders as well as attacking ones."