Chelsea manager Carlo Ancelotti will be without centre-back Alex and midfielder Ramires for the next two games because of hamstring injuries.
The pair missed last Saturday's win at West Brom and will now also miss home games against Birmingham and West Ham.
Meanwhile, Ancelotti insists Fernando Torres will break his Blues goalscoring duck before the end of the season.
The £50m Spain striker has gone 871 minutes without a goal but Ancelotti insisted: "He will score."
However, the Italian refused to confirm if Torres would start for the Blues against Birmingham on Wednesday.
Chelsea's attack was spearheaded by forward Didier Drogba in a 4-3-3 formation in the 3-1 win at West Brom and the Ivory Coast international scored, as well as playing a part in his side's other two goals.
Torres, along with fellow striker Nicolas Anelka, was on the bench at the Hawthorns before coming on to make a late cameo appearance.
"It's very difficult to change the team that played so well against West Brom, not just for the result, not just for the performance," said Ancelotti.
"They did very well against West Bromwich."
Torres had a strike disallowed for offside in his substitute outing at West Brom as his frustrations in front of goal continued following his move to Chelsea from Liverpool in January.
"We are working with him like we are with the other strikers," added Ancelotti.
"He has exercises to score - shooting, crossing - but nothing different from the others.
"I think he wants to score and he's not happy for this reason. I would like to see my players every time happy and with confidence.
"It's not a good moment for Fernando, but I want to do my best to support him."
Meanwhile, Ancelotti does not believe the uncertainty over his position will result in the Stamford Bridge club's players easing off for the final six games of the season.
Ancelotti revealed he would not have a "problem" if the club sacked him during the summer after what could be the club's worst season under owner Roman Abramovich.
Chelsea won a Premier League and FA Cup double in the Italian's first campaign in charge last season but have faltered in their defence of both, as well as having been knocked out of the Champions League at the quarter-final stage.
"They are Chelsea players, they are professional," he said. "This is football, that sometimes the manager can change.
"They are working with me at this moment. Maybe they will work with me in the future. Maybe they will not work with me in the future, but with another coach."