Mclean suffered a spasm in his hamstring during Wednesday night's enthralling Capital One Cup win over Leeds United, while both Liddle and Kennedy picked up knocks after being on the receiving end from a couple of robust tackles from Leeds players.
Loan duo Mason Bennett and Jordon Pickford will definitely be available for selection, however, after being ineligible for the Leeds tie.
Bantams assistant Steve Parkin said: "We have a few niggles around.
"Jason Kennedy and Gary Liddle both got a bit of knock after the challenges they received on Wednesday. Aaron (Mclean) felt his hamstring a wee bit in the game but he was feeling a lot better yesterday (Thursday).
"It is definitely going to be a case on Saturday of selecting a team that is as fresh as possible and ready to go again.
"All the lads at the moment, those involved on Wednesday and those not involved, are really focused. They are a terrific set of lads and they seem to have moved on from the Leeds game already.
"That are now focused on the job in hand this Saturday."