Left-back McCrory and leading scorer Zola have missed the last two matches with ankle and hip problems respectively.
McCrory returned to training this week and Zola has a chance of being in contention on Saturday.
Burton were down to the bare bones for the visit of Rotherham last weekend but several men played through the pain barrier as Gary Rowett's team triumphed 2-0.
Aaron Webster (calf), Nathan Stanton (knee), Anthony O'Connor (ankle) and Alex MacDonald (dead leg) all played despite carrying knocks and all four have had two days off this week to recover.
Club captain John McGrath, on the bench against Rotherham, has joined Albion's npower League Two rivals York on loan, while on-loan Millers centre-half Ian Sharps comes back into the reckoning after being ineligible against his parent club.