Sam Hutchinson is to undergo surgery on his troublesome knee injury.
The midfielder returned to the squad at Bolton recently after a knee problem but then missed last Saturday’s defeat at Derby through illness.
Carlos Carvalhal said at Thursday’s press conference that Hutchinson had suffered another problem with the knee and he revealed after the 1-1 draw at Barnsley that the player now faces an operation.
The head coach added that he does not know how long Hutchinson is likely to be sidelined for.