Chelsea head coach Carlo Ancelotti has confirmed that striker Didier Drogba has been carrying a groin injury for some time and may yet need surgery at the end of the season.
The 32-year-old Ivory Coast international sat out last weekend's 7-1 drubbing of Aston Villa, but is expected to return for the crunch clash with Manchester United on Saturday.
Ancelotti told reporters: "Drogba has been living with this problem for three or four months, but it is not a big problem.
"Sometimes he has problems after the game, but during the week he doesn't have any difficulty.
"He will not need surgery now and if he needs to have an operation at the end of the season he will be ready in seven days because it will be a very little surgery - but I don't know if he will need to have that surgery.
"He was a little bit tired before the last game against Aston Villa, so I didn't want to take the risk to put him on the pitch, but now he is fit and he has to play."