Birmingham have moved to cover a minor defensive crisis with the capture of experienced left-back Paul Robinson.
Left-back David Murphy and centre-half Pablo Ibanez were both ruled out for a month with injuries sustained during City's 5-0 home defeat to Barnsley at the weekend.
But Blues boss Lee Clark has brought in Robinson on a one-month contract with the 33-year-old a free agent following his release from Bolton at the end of last season.
Clark told the club's official website: "I'd like to thank the Board for allowing me to bring in Paul, an experienced defender who will enhance our playing squad.
"While I have been impressed with the progress of our young defenders, recent injuries had left us with just two fit senior defenders so the acquisition of Paul was one we needed to make.
Murphy, 28, hobbled off after just 25 minutes of Saturday's rout at St Andrews and scans have revealed he has torn a hamstring and he is now facing up to four weeks in the treatment room.
Ibanez is set for a similar spell on the sidelines after it was confirmed the Spaniard broke a bone in his foot during the second-half against the Tykes.