Cole Palmer faces a further six weeks on the sidelines as he fails to recover from a lingering groin issue.
The Chelsea star has missed his side's last four matches in all competitions due to the problem, which saw him absent for two games at the start of the campaign.
Cole Palmer with Chelsea assistant coach Willy Caballero
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Palmer has missed six games this season in total due to groin issuesCredit: Getty
It had been hoped that the 23-year-old would be fit to feature after the October international break.
The Blues travel to Nottingham Forest in Saturday's 12:30pm kick-off - live on talkSPORT.
But boss Enzo Maresca has confirmed that the west London outfit will once be without their talisman.
What has Enzo Maresca said about Cole Palmer?
Speaking in his pre-match press conference, the Italian said: "I was wrong [about Palmer returning in October].
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"Unfortunately he needs to be out for six more weeks.
"We try to protect Cole as much as we can.
"The most important thing is when he comes back, he is fully fit.
"The medical staff are not magicians, we hope six weeks are enough.
"We need to see it step by step, for sure, he's going to be OK."
Palmer's groin issue was highlighted in August, when he was withdrawn from the starting line-up away at West Ham just minutes before kick-off.
Maresca has revealed that Palmer is set to be out for a further six weeks
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Maresca has revealed that Palmer is set to be out for a further six weeksCredit: AFP
And in his second game back after his first spell out of the team, he limped off against Manchester United.
England boss Thomas Tuchel has already expressed concern that Palmer's problem doesn't become 'chronic'.
And while Maresca is confident Palmer's long-term fitness will be fine, his absence represents a major loss for Chelsea.
Before the November international break, the Blues face Forest, Sunderland, Tottenham Hotspur and Wolves in the Premier League.
They also test themselves against Ajax and Qarabag in the Champions League, as well as Wolves in the Carabao.
More to follow...