Striker Ross McCormack could be facing an extended period on the sidelines.

The striker will undergo surgery on his ankle on Friday and will have to wait until after the operation before learning the severity of the problem.

"The surgeon has had another look at the scans and he is concerned," said boss Neil Warnock, whose initial thoughts were that the Scot could be out for around six weeks.

"We thought it was a fragment of bone, but it could be a little bit bigger than we thought so the prognosis is it could be another four weeks or so but we won't know until he goes in and operates, and we'll know the decision then.

"The worst scenario could be the best part of Christmas which isn't good for us. He is a player you can't replace. We wish him all the best and hope he's back as quick as possible."