Tottenham Hotspur midfielder Tom Huddlestone will miss the rest of the season as he requires further surgery on an ankle problem, manager Harry Redknapp said before Sunday's trip to League One Stevenage.
Redknapp, whose side are favourites for the trophy as Manchester United and Manchester City have been knocked out, said he would field a strong team for the game.
"I've got one or two I'd like to play. Ryan Nelsen has come in, the lads have said that he's trained great this week. I've always been a big fan of his, I think he's a great competitor," he said on the club's website.
Chelsea expect to have midfielder Ramires back for Saturday's match at home to Championship Birmingham City but captain John Terry remains doubtful.
"With such a short distance between... two games we must be careful. If he [Terry] plays against Birmingham then he may not be able to make the Napoli game [in the Champions League] so we haven't made a decision yet," manager Andre Villas-Boas said.
The club will be glad for a brief respite from Premier League matters, where they have slipped to fifth, leading striker Didier Drogba to tell local media it would be a "disaster" if they finished outside the top four.
Arsenal midfielder Mikel Arteta has urged his team-mates to be wary of the threat of counter-attacking before they travel to Sunderland on Saturday after the Londoners suffered a 4-0 defeat by AC Milan in the Champions League this week.
"We've been counter-attacked too many times playing away from home and we cannot allow that to happen," he said on the club's website.
"That was the key. Milan scored three goals on the counter-attack and we are very disappointed. It is difficult to take in and we have to change our mindset because we have another tough game on Saturday."
Midfielder Maxi Rodriguez could return for Liverpool's match at home to Championship Brighton & Hove Albion on Sunday after recovering from a foot injury.
"Maxi is back training," Liverpool manager Kenny Dalglish said on the club's website. "He had a kick on his foot in training but he's fine now. Everybody who is fit is in our thinking for Sunday."
Defender Jamie Carragher will equal Ian Callaghan's club record of 210 cup games if he faces Brighton.
Bolton Wanderers captain Kevin Davies has been ruled out of Saturday's game at Championship outfit Millwall.
"The skipper picked up a medial ligament injury in the first half of last week so he will miss out," Bolton manager Owen Coyle told reporters.
"We are hopeful that he will be a couple of weeks maximum and that he might be available for Chelsea next weekend."
