Chelsea interim manager Rafa Benitez admits he has "no idea" when captain John Terry will return to fitness.
Terry has been out of action ever since sustaining a knee injury in the 1-1 draw with Liverpool at Stamford Bridge on November 11.
A return date was originally set for December, but the centre-back remained sidelined and missed the Blues' trip to Japan to compete in the FIFA Club World Cup just before the Christmas period. Now in January, the former England skipper is still yet to resume full training, and Benitez admits that he does not know when the 32-year-old will be available again.
"I talked with John on Wednesday morning and he is getting there and can start to do the warm-up with the team soon and then we will see how he will progress," Benitez is quoted as saying in the Daily Mirror.
"Talking to the doctor, the problem is a build-up of fluid on the bone. So at this stage we have no idea when he will be back."
Benitez is also facing problems involving several other key players. Goalkeeper Petr Cech is set to be out for up to three weeks with a groin injury while Nigerian pair John Obi Mikel and Victor Moses will soon be departing for the African Nations Cup.
However, the Blues could be boosted by striker Demba Ba completing his transfer from Newcastle in time for Saturday's FA Cup tie at Southampton after the Senegalese completed his medical without a hitch.
"If we can do the business I hope he can play in the FA Cup," Benitez added.