Bolton's on-loan defender Dedryck Boyata will be sidelined for up to six weeks with an ankle injury.
The Manchester City player sustained the knock during the second half of last weekend's 2-0 loss to Sunderland.
"Dedryck is going to be out for up to six weeks with ankle ligament damage," said Bolton manager Owen Coyle.
"It's a shame, first and foremost for Dedryck because he has shown what a top player he is capable of being, and then secondly for the team and the club."
Coyle added: "Part of the arrangement in the loan contract was that, if an injury did occur, then he would report back to City and liaise with our club doctor and the medical team here. That is what will happen."
Belgium international Boyata joined the Trotters on a season-long loan in August.