Chelsea's Portugal international centre-back Ricardo Carvalho could be sidelined for up to two months due to a back problem sustained in the 1-1 draw with Everton.
Carvalho had to be replaced after half-an-hour of the weekend action, with Blues manager Avram Grant already having Petr Cech, Paulo Ferreira, Ashley Cole and skipper John Terry out of action at present.
The seriousness of Carvalho's injury was confirmed by Portugal Football Federation doctor, Henrique Jones, who said: "It is not a serious injury but Ricardo should rest for at least eight weeks.
"Ricardo has suffered fractures of the small bones on his second, third and fourth vertebrae."
Grant had previously stated: "One month ago the goalkeeper and the back four were different players. We have too many injuries.
"It is not easy to play without all the back four and goalkeeper from the last few months. This is the reason we have a big squad."
Meanwhile, Blues boss Grant has also confirmed that he has held talks with two members of his squad, who are unhappy at Stamford Bridge at the current moment.
He added: "Sometimes players come to me and say they are unhappy. Two have done this, but it doesn't matter who."