Alex McLeish may gamble on playing Birmingham City defender Roger Johnson in Tuesday's home Carling Cup clash with Brentford even though he is nursing a calf problem.
Johnson has been dogged by the injury for several weeks and McLeish wanted to rest the former Cardiff player ahead of Sunday's derby with Aston Villa.
But thigh and hamstring injuries to back-up defenders Martin Jiranek and David Murphy means Johnson is likely to play as Blues look to book their quarter-final spot.
Blues manager McLeish admitted: "We've got one or two knocks and one or two players running on empty and we have to be careful we don't burn them out.
"For instance, Roger Johnson has been playing with a calf problem for a while and, normally with calf injuries, you would be ruled out.
"Johnson is a different type of animal. He will play through things. You get characters like that, some guys have got higher pain thresholds than others.
"If we keep putting Johnson through the mill than we could lose him for longer But a couple of the players who would have come in have taken knocks in Murphy and Jiranek. I wanted to rest Johnson. Whether I can do that now is debatable."
McLeish knows Blues have a golden opportunity to reach the last eight of the competition but insists Brentford will be no pushovers after their shock win against Everton.
He said: "Why not think of reaching Wembley? We've got to think that way but we do realise there are some incredible competitors out there.
"But first and foremost, let's get through this one because if we don't there is no point even chatting about that.
"We have to give Brentford every respect and not approach the game in a complacent manner and the gauntlet is down for the players who come into the side.
"For Birmingham to win a trophy would be a dream come true. We are not a fashionable club in terms of being trophy winners
"We are a good old traditional English club in the true sense of the word and it would be nice for Birmingham to have a bit of history but we are a long way from that.
"It is nice to talk about it but talk is cheap. You've actually got to go and do it on the pitch."
McLeish added: "Brentford have got nothing to lose. They are coming to a Premier League team. They can come relaxed knowing if they lose, it is expected, but if they win, then it is utopia for them.
"We know that has been the approach of the teams we have already knocked out of the cup with Rochdale and MK Dons putting in excellent performances.
"They raised their games and Brentford will do the same."
Former Sporting Gijon play-maker, Michel, will be given a rare start by McLeish after the form of Barry Ferguson has kept him out of the starting line-up.
McLeish said: "It is a bit of a thankless task for Michel because he was the captain of Sporting Gijon and we saw him play really well against the Real Madrids and Barcelonas of this world.
"But Ferguson's form has been exceptional and I've not devised a system where I can get the two of them into the same team.
"I know there are ways of doing that but I don't think it suited the rest of our players.
"Michel has been extremely unlucky. He wouldn't have envisaged being understudy to Barry. He may have thought he could have played in the team with Barry.
"It has been tough for him but at the end of the day we need a squad and I need cover for Ferguson and other players."