Former Newcastle and Tottenham full-back Stephen Carr is currently training with Birmingham with a view to joining the Coca-Cola Championship promotion hopefuls.
The ex-Republic of Ireland international, 32, retired in December but he has offered his services to Blues in light of their current problems at right-back with Stuart Parnaby sidelined due to a thigh injury and Stephen Kelly on loan at Stoke.
"Stephen Carr has been training with us," McLeish told www.blues.co.uk. "He's not played since the summer and that's the downside. But he looks fit enough and he's been looking after himself."
He added: "Of course when you've been out that long it's a tall order to come straight back in and be at your sharpest along with the rest of the players who have played all the way through the whole season.
"Stephen made the announcement that he was retiring in December because I think there were no other offers. But a couple of pals of his that I know said he would come back if he got the opportunity.
"When we had this right-back situation his pal phoned and said he would come in and train with us. We've got a lot of plates spinning at the moment to see what we can do to improve things."
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