Birmingham will be without David Murphy for Sunday's home clash against play-off rivals Cardiff.
The left-back saw red in Tuesday's shock 4-1 defeat at Portsmouth and will now serve a one-match suspension as seventh hosts eighth at St Andrew's, kick-off 12noon.
Murphy's absence provides manager Chris Hughton with yet further selection problems at full-back, with Stephen Carr (knee) and Jonathan Spector (thigh) still out.
Peter Ramage is expected to cover Murphy at left-back, with one of Curtis Davies or Pablo Ibanez likely to fill in at right-back and the other to play in their more natural position alongside Steven Caldwell at the heart of defence.
Davies, however, is now treading a fine line himself having received his ninth booking of the season at Fratton Park, meaning he is one more away from an automatic two-match ban.
Midfielder Keith Fahey was also forced off against Pompey nursing injury and will be assessed but Blues are boosted by the returns of on-loan striker Erik Huseklepp, who was ineligible in midweek, and midfielder Jordon Mutch, who has completed his three-match suspension.
Cardiff are, however, sweating over the fitness of striker Kenny Miller ahead of their clash with Birmingham.
Miller missed the 2-2 draw with Coventry in midweek because of a minor ankle injury but could make his return to the matchday squad at St Andrew's.
However, Miller, who has not scored in any of his last 12 appearances for the Welsh club, faces competition from Rudy Gestede and Robert Earnshaw for a place up front.
Stephen McPhail recovered from illness to make his first start of 2012 against the Sky Blues on Wednesday and the midfielder should be available once again to manager Malky Mackay, who has yet to give up hope of making the play-offs.