Benoit Badiashile has been ruled out until December as Chelsea continue to be plagued by defensive injuries.
The French centre-half impressed in the2-1 win over Liverpool in the last Premier League game before the international break.
But he had to go off in the second half of the game and now faces a spell on the sidelines.
Boss Enzo Maresca, speaking ahead of Saturday’s away match against Nottingham Forest, said: “Unfortunately, Benoit will be out until December.
“He has a muscle problem. He was doing fantastic and showing how good he is and how much we need him.”
The Blues are already without Levi Colwill, who will be out for most of the season with a long-term knee injury, while Tosin Adarabioyo, Wesley Fofana, Trevoh Chalobah and Josh Acheampong have all been struggling for fitness.
And there are also injury concerns in midfield and attack – Moises Caicedeo, Enzo Fernandez and Pedro Neto are all doubts for the Forest game.
“Moises, Enzo and Pedro didn’t train [on Thursday] so we will see if they can train, otherwise they will be out tomorrow,” Maresca explained.
Meanwhile, Cole Palmer faces another six weeks out with his troublesome groin problem.
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