Cardiff have eight senior players out injured. They are listed below.
Also unavailable are Kadeem Harris - suspended. And Matt Connolly has mysteriously been loaned to Watford. He played against Bournemouth for Cardiff on Tuesday in place of the injured Lee Peltier but we have loaned him out? Bizarre.
David Marshall (groin): Rated 50-50 again. Won't be risked until he is 100% ready.
Lee Peltier (hamstring): Rated 40% at best to be ready against Birmingham. The match will come too quickly for him.
Anthony Pilkington (hamstring): Has suffered a couple of setbacks in training and is still a few weeks away.
Conor McAleny (hamstring): Highly unlikely to be back on Saturday, but should be available after the international break.
Nicky Maynard (knee): Still some way off returning to the Cardiff squad.
Joe Mason (hamstring): Will play at under-21 level on Friday. He'll be given 45 minutes or so, a first outing in four months, but don't expect him back in the first team for a while.
Kagisho Dikgacoi (muscle problems): Is to join Mason in the under-21 team to play at Brentford. Has played only three times since last May - and is a long way from full match fitness. He has been in full training and it is hoped he will get through half a game on Friday. Like Mason, he won't be back at first team level for some time yet.
Ben Turner (ankle): Certain to be out for some time yet. Making progress, but may miss the rest of this season.