Midfielder Alan McCormack is back in training ahead of Sunday’s Emirates FA Cup third round tie at Burton Albion but Harry Smith (ankle) and Shaun McWilliams (knee) are both expected to be out for the next two to three months.
“Alan is back training on the grass and we will assess him before Sunday,” said boss Keith Curle.
“Shaun and Harry are both fairly long-term and the initial diagnosis with them is they will be out for 8 to 12 weeks.
“Neither of them needs an operation which is good news but the first three or four weeks of their rehabilitation is vital and that will set the tone for their recovery.
"We will keep assessing things but our initial thoughts are absences for each of them of 8 to 12 weeks.
“We are always looking to improve the squad and I think we need goalscoring options, whether that is up front, in midfield or out wide.
“Having said that, we have an understanding of where we are and we know we need to maintain good housekeeping.
“We need value for money in any business we do and we can’t and won’t overspend.”