SHAUN Williams and Ben Thompson have stepped up their recoveries from injury but neither are expected to be available for this week's Championship games against Birmingham and Bristol City.
Ryan Leonard is also set to be unavailable for both games after picking up a hamstring problem.
That leaves Lions boss Gary Rowett with just Ryan Woods and Jayson Molumby in central midfield, and Billy Mitchell, who has yet to start a league game, as back-up.
Thompson has been out since December with ankle ligament damage, while Williams has missed the last three games with a hip injury.
Rowett said: "Thommo has been outside doing a little bit of ball work and jogging. He feels good but at the same time he's been out for a while so we've got to make sure we take the necessary precautions.
"Both he and Willo in different ways have been outside and working and hopefully it won't be too long before either of them join in training.
"Willo won't been available this week, nor will Lenny. We think there might be a little bit of a tear in his hamstring so he won't be available for the next two games, we think.
"Thommo is obviously nowhere near it yet.
"That's just where we're at. Depending on which formation we play we've got quite a few options in some areas but limited options in others.
"There's been a few times when one of the centre-halves has been injured and we can't play a five at the back, we've had to change the formation because we haven't had enough bodies."
Image: Millwall FC