Winger Kadeem Harris’ red card at Brentford last weekend means he definitely misses out along with long-term absentees Joe Mason (hamstring), Ben Turner (ankle), Nicky Maynard (knee), Anthony Pilkington (hamstring) and Kagisho Dikgacoi, who is working his way back to full fitness after muscle problems.
Simon Moore is set to continue in goal with Scotland international David Marshall unlikely to be risked as he closes in on a comeback from a groin injury while Lee Peltier is set to miss out once more with a hamstring problem.
Another hamstrung player, attacker Conor McAleny, is likely to join Peltier on the sidelines but there is a welcome return for Federico Macheda after he served his one-game suspension in Tuesday’s draw with Bournemouth.
Birmingham have been boosted as Matt Green and Gavin Gunning edge closer to fitness.
The duo will not be considered against Cardiff but will play in the under-21s on Monday after long-term knee injuries.
Michael Morrison remains a doubt with an ankle problem but has returned to training.
Stephen Gleeson is available again after serving a three-game ban for a red card.