Gardner, Blues' leading scorer, will also be unavailable for the games against Arsenal and Blackpool after his straight red card against Wigan last weekend.
Blues boss Alex McLeish could switch Lee Bowyer from the left flank back into his preferred central midfield position alongside Barry Ferguson.
Keith Fahey will be in contention for a recall after not starting a league game since the opening day of the campaign at Sunderland.
Source: PA
Source: PA