Chelsea manager Rafael Benitez has confirmed defender Gary Cahill underwent knee surgery recently, but is tipped to make a full recovery in the coming weeks.
Cahill, 27, suffered the injury during Chelsea's win over West Ham last month and was forced to withdraw from England's World Cup qualifiers aganist San Marino and Montenegro.
Benitez expects Cahill to require just a further two weeks on the sidelines, keeping him in line for the Europa League semi-finals if Chelsea progress.
"He had an operation," Benitez said. "We did it very quickly on the Saturday of the Southampton game (March 30)."
The Blues are also expected to be without defender Ashley Cole who was substituted off with a hamstring injury in the FA Cup defeat of Manchester United last week, although Benitez is confident both are recovering quickly.
"The feeling from both is really good," he said.
Chelsea's back line heads to Moscow for the second leg of their Europa League quarter-final against Rubin Kazan on Thursday looking significantlly depleted, with Ryan Bertrand also in doubt due to illness.
Benitez will be forced into a number of changes as Chelsea look to hold on to their 2-1 first leg lead and while Demba Ba will not be available for Thursday's match due to injury and his previous involvement in the competition with Newcastle, he is expected to return for the FA Cup semi-final against Manchester City this Sunday.
"Demba Ba did not train today, just as a precaution," Benitez said. "It's not too serious. He will not go to Moscow. Hopefully he can train here and be okay for the weekend."
Information from the Press Association was used in this report.