Chelsea manager Enzo Maresca has confirmed that midfielder Romeo Lavia won't be fit to face Fulham in the Premier League this week.
The Belgium international picked up a hamstring injury earlier last month and this has kept him on the sidelines for a number of matches.
The former Southampton man has returned to training recently, but Maresca insists that he is not ready for the upcoming west London derby.
He said: "Romeo is still recovering. He's much, much better. He's already working on the pitch but unfortunately he's not ready [for Fulham]."
The Blues recently suffered a dip in form with a goalless draw at Everton. As a result, they are four points behind leaders Liverpool, who have a game in hand.
Chelsea need to return to winning ways against the Cottagers at home on Boxing Day to keep up the pressure on the Reds in the title race.
Aside from Lavia, Reece James, Wesley Fofana and Benoit Badiashile will also be missing against the Cottagers with hamstring injuries.