Midfielder Ryan Watson is set to undergo surgery on Friday after suffering a broken collarbone against Peterborough in midweek.
“We wish him all the best for his recovery,” said boss Keith Curle.
“Alan McCormack is stepping up his training and we are hoping to arrange a game for him next week. We train and play at a high tempo and we need to make sure Alan is robust enough when he comes back into the team.
“The squad is still looking competitive and I don’t think many teams would be able to say that with arguably four or five potential starters unavailable
“Just because the window is shut doesn’t mean we aren’t still looking, there are players still available and the planning has already started for the next window in January.”