Chelsea's preparations for Sunday's top-of-the-table battle with Manchester United have been hit by another injury to Frank Lampard.
The England midfielder is expected to be sidelined for "a number of weeks" after suffering a recurrence of his calf strain against Shakhtar Donetsk.
Blues manager Roberto Di Matteo confirmed that Lampard will miss Sunday's fixture at Stamford Bridge as well as the Carling Cup tie against United on Tuesday.
Lampard is also expected to miss next weekend's trip to Swansea and the return Champions League clash against Shakhtar on 7 November.
Di Matteo did not put a timeline on a possible return date for Lampard, but it is clear the England midfielder will not be rushed back.
"He is going to be out for a few weeks. He's got a calf problem, so we will miss him and it's a big loss for us," said Di Matteo, who reported no further fitness problems in his squad.
He added: "Apart from Frank, everybody else is fit. Marko Marin might be in the squad for Sunday."