Birmingham's Alexander Hleb is facing a scan on the hamstring he injured against Fulham and is unlikely to be fit for Wednesday's match.Manager Alex McLeish is likely to field the strongest side he has available to him, despite picking reserve sides in previous rounds.
Aston Villa's James Collins is expected to be fit despite aggravating a calf problem against Arsenal on Saturday.
They remain without 10 players through injury or illness.
MATCH PREVIEW
These bitter rivals lock horns for the 11th time in cup competitions. Birmingham have managed just one win over Aston Villa in their previous ten cup clashes but what a win it was for the Blues as they lifted the only major trophy of their history by winning the 1963 League Cup.
The closest they have come to winning something since ended in disappointment when a Liverpool side, managed by Gerard Houllier, beat the Blues on penalties in 2001.
Now in charge of Villa, the Frenchman's start to life at the club has been beset by injury problems within his squad. But despite having 10 first-team players out, they stand on the brink of reaching the League Cup semi-finals for a record 14th time.
Birmingham boss Alex McLeish has been blas?bout this competition and would put league survival above the chance of silverware stating: "If we lifted the Carling Cup and we were relegated, that would be a disaster," he said. Whether Birmingham's fans see it in quite such black and white terms is debatable, but a win over the old enemy always goes a long way to defining a season.
MATCH FACTS
Head-to-head
• This is the 120th competitive meeting of these sides. Birmingham have won 37 of the previous 119, Aston Villa 52, with 30 finishing level.
• Villa had won their last six against Birmingham until a goalless draw in the Premier League on 31 October.
• The Blues have not scored in their last three meetings with Villa, and have not beaten their rivals since a 2-0 home triumph in the top-flight in March 2005.
• Birmingham's only cup win over Villa in 10 attempts came in the first leg of the 1963 League Cup final. The Blues won 3-1 and then drew the return leg to lift their only major trophy to date.
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Birmingham
• They are playing in the quarter-finals for the first time in five seasons, and are targeting a fifth semi-final appearance, and their first since finishing runners-up in 2001.
• Alex McLeish's side have won only two of their last eight outings in league and cup, but have avoided defeat in seven of those matches.
• Birmingham have won two and drawn two of their last four home games, and have not lost in front of their home supporters since Everton's 2-0 Premier League victory on 2 October.
Aston Villa
• Aston Villa, last season's runners-up, are looking for a record 14th appearance in the League Cup semi-finals.
• This is Villa's first away tie in this season's competition, having already defeated fellow Premier League Blackburn and Championship Burnley at Villa Park, although the latter took them to extra time.
• Gerard Houllier won the League Cup with Liverpool 2001 and 2003.
Source: BBC Sport
Source: BBC Sport