Doncaster Rovers pair James Coppinger and Brian Stock will not play again this season due to injury.
Coppinger has been ruled out for at least six weeks after suffering an ankle injury in last week's defeat against Reading, although he is unlikely to require surgery.
Rovers captain Stock is out for similar period due to a persistent back injury which will see the midfielder undergo an operation.
Sean O'Driscoll acknowledged his disappointment at losing the duo and could now move into the loan market to bring in replacements.
"It's a big blow for us," O'Driscoll told the club's official website.
"James Coppinger has got a flake fracture and he has done various ligaments. Touch wood, he won't require surgery, but he will be at least six weeks and Brian is the same.
"At a push, we could probably get Brian back for the Wolves game, but you would be taking a chance on a back injury, so we have written them off for the rest of the season.
"Brian's surgery has been booked, then un-booked, then booked, then un-booked and he has done fantastic to play as many games as he has. But he will be going in for the operation now, so that the quicker we get him in, the quicker we'll get him back.
"We'll look into the loan market, but the difficulty is finding somebody that fits the bill at this late stage of the season and whether we can afford it financially as well."