Captain Steven Caldwell will be assessed ahead of Birmingham's home clash against Derby at St Andrew's in the Championship on Saturday but fellow defender Mitch Hancox has been ruled out.
Centre-back Caldwell battled through illness to start last weekend's 5-2 defeat at Hull before coming off in the 37th minute and duly missed Tuesday's 1-1 draw at home to Blackpool, with the Scot returning to training for the first time on Friday.
Left-back Hancox sustained a hamstring injury against the Seasiders which saw his involvement cut short in the second half and he is now sidelined for three weeks.
Boss Lee Clark said: "It was a blow when young Mitchell had to come off with a tight hamstring. It's a bit of a nightmare for us, you just get things going the way you want them to and you get a setback."
Spanish defender Pablo remains sidelined through injury while leading scorer Marlon King has been ruled out for the remainder of the season with a knee problem but midfielders Keith Fahey and Darren Ambrose could be involved.
Derby hope to have Craig Bryson fit for their trip across the Midlands to face Birmingham.
Bryson missed the 1-1 draw at Championship leaders Cardiff on Tuesday night with a groin injury and the midfielder will continue to be monitored ahead of the weekend.
The Rams' other injury problems do not look like clearing up in time for the St Andrew's clash, though.
Jamie Ward was absent in the Welsh capital after a hamstring problem forced him off during the home defeat to Crystal Palace last Friday. The diminutive forward could be back in the squad when Leicester visit Pride Park on March 16.
John Brayford was an ever-present in Nigel Clough's team until a hamstring injury ruled him out against Cardiff. The extent of the problem is not yet known but the right-back could be looking at several weeks on the sidelines.
Fellow defenders James O'Connor (knee), Kieron Freeman (ankle) and Mark O'Brien (knee) are not ready to return, while no comeback date has been put on teenage midfielder Will Hughes (groin).
Billy Clarke should return to the Red Devils squad after their 12-goal top scorer resumed training following a hamstring injury ahead of Tuesday night's clash with Carlisle, but was not risked for the 1-1 draw.
Boss Richie Barker is still without captain Josh Simpson due to an ankle injury, while defender Kyle McFadzean remains sidelined as he recovers from the virus which struck him down in November.
Mark Connolly may have to settle for a place on the bench again.
The defender returned from a one-game suspension against Carlisle but Barker kept faith with January signing Connor Essam, who impressed on his full debut in Saturday's 2-0 win at Bury in Connolly's absence.
The Magpies are without the suspended Dean Leacock, who received his 10th yellow card of the season during the 1-1 home draw with Leyton Orient on Wednesday night and will begin a two-match ban.
John Cofie suffered a facial injury against the O's and the striker is a doubt along with right-back Julian Kelly, who has missed the last two games with a calf problem.
Manny Smith could come in for Leacock while Yoann Arquin, Cofie's 42nd-minute replacement in midweek, is on standby should the on-loan Manchester United youngster miss out.
Midfielders Jeff Hughes, Hamza Bencherif and Greg Tempest are also options for manager Chris Kiwomya should he wish to make any further changes to his starting line-up.
