Ben Chilwell had to be helped from the pitch by two physios against Juventus
Chelsea defender Ben Chilwell will be out for at least six weeks with a knee injury but the Blues hope he will not need surgery.
The 24-year-old England left-back suffered the problem in Tuesday's 4-0 Champions League win against Juventus.
"Ben has a partial injury of his ACL," said Chelsea boss Thomas Tuchel.
"The next six weeks will tell the story actually if he makes it and if he will be fully available after the six weeks, or if he needs surgery after that."
He added: "Right now I only care about the six weeks. We are very positive because the first reaction of his body is very positive.
"Hopefully it stays like this so now the full focus of everybody is on the next six weeks, to try to bring him back to play.
"It's a very responsible decision, so there's no rush, no pressure."
Chilwell has been in impressive form, with three goals and one assist for the Blues this season.
"This for him personally is a very bad moment, because he was so good and so full of confidence," said Tuchel, whose side are top of the Premier League and host Manchester United on Sunday at 16:30 GMT.
"He was a huge part of our performances and victories in recent weeks. It's a shame and very sad.
"But he's actually in the moment very positive, because his body reacted very positively to the first treatments and to the injury.
"So after a while you have to refocus, and focus on the positive things. And that's now the next weeks, to do everything possible he can to come back and help us on the pitch."
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