Midfielder David Norris has emerged as a doubt ahead of Tuesday night's trip to Birmingham City due to a dead leg sustained in Saturday's 2-0 victory over Derby County. Full-back Moritz Volz is back after a one-match ban, while skipper Gareth McAuley could also return.
Boss Jim Magilton says Norris appears unlikely to make the trip to St Andrew's: "David is struggling to be fit. He has a dead leg which is still sore and we know how painful they can be.
"We will give him every chance and another 24 hours might help but he is a doubt.â€Â
Central defender McAuley wasn't far from being involved against Derby on Saturday and may be OK to return to the side, although Alex Bruce and Richard Naylor had few problems against the Rams on Saturday and could keep their places.
Magilton has to decide whether to recall Volz after his one-match ban, with David Wright impressing at right-back after a spell at left-back. Ben Thatcher was solid if unspectacular on the left against Derby and it could be that Magilton sticks with the full-back pairing which helped see the Blues to a clean sheet at the weekend.
If Norris misses out in midfield, Jon Walters may switch to midfield from his striking role, perhaps with the Blues moving to 4-5-1 with Tommy Miller also coming into the reckoning. However, the Town manager has preferred to use Walters in attack in recent weeks and may prefer to keep him there and look at other midfield options.
Darren Ambrose could move from the left to the right with Alan Quinn returning to the side, while Danny Haynes is perhaps an outsider for the role. Owen Garvan and Veliche Shumulikoski were back to their best against the Rams on Saturday and look set to continue their central midfield partnership.
Up front, Magilton is likely to continue with Walters and Couñago unless he moves the former Chester man to midfield, in which case the Spaniard could be up front on his own or Jon Stead could be in line for a recall to the line-up.
Birmingham, currently second in the table, 10 points ahead of the Blues in eighth, will have midfielder Nigel Quashie back after a one-match ban, while left-back David Murphy returned to the bench against Swansea on Friday after a spell out with a knee injury.
Right-back Stephen Kelly is also close to a return to the first team after a thigh problem, but winger Gary McSheffrey continues to be sidelined with a knee problem.
Midfielder Damien Johnson has a long-term back injury, while striker Garry O'Connor's groin has kept him out of action since October.
Town have had the edge on the Midlanders over the years, winning 30 games (27 in the league), losing 24 (18) and drawing 11 (11).
The teams last met in 2006/07 when a last minute Gavin Williams goal gave the Blues a 1-0 victory at Portman Road. Earlier in the season at St Andrew's, David Dunn had grabbed a late equaliser for his side in a 2-2 draw after Alan Lee and Simon Walton had scored for the Blues and DJ Campbell had netted for the home team.
Birmingham's Bruno N'Gotty was memorably red-carded for kicking out at Alan Lee after the Town frontman had scored his goal.
Marcus Bent is the only former Blue in the Birmingham squad at present, although Kevin Phillips famously almost joined Town prior to signing for Sunderland in the summer of 1997. Alex Bruce was a Birmingham player during his father's time as manager at St Andrew's.
Tuesday's referee is Rob Shoebridge from Derbyshire, who has shown 37 yellow and three yellow cards in 17 games so far this season. Shoebridge has not previously taken control of a game involving Town or Birmingham.
Likely squad: R Wright, Supple, D Wright, Thatcher, Volz, Naylor, McAuley, Bruce, Balkestein, Garvan, Shumulikoski, Ambrose, Norris, Quinn, Miller, Walters, Couñago, Stead, Lisbie, Haynes.