Captain Brian Stock and striker James Coppinger will both play no further part this season, with Stock giving in to a persistent back problem and Coppinger falling foul of an ankle injury suffered against Reading last week.
"It's a big blow for us," manager Sean O'Driscoll told his club's official website. "We've got a bit of time now, where not only can we - to an extent - come to terms with it but also get the best out of the players that we've got.
"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.
"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. To be fair to the lad, he's done everything he possibly could."
O'Driscoll also added that he'll look to bring in replacements on loan, but only if the club can afford it.