Mason Mount is expected to undergo tests and further checks on an injury he picked on Tuesday night against Ajax in the Champions League.
The England international will have scans today, Wednesday, to determine the extent of the injury, which might see him miss the match against Crystal Palace as well as England's final two Euro 2020 qualifiers.
Mount was withdrawn on the 60th minute of the pulsating 4-4 draw against the Dutch side and was suspected to have suffered an ankle sprain.
Manager Frank Lampard, who spoke after the game, could not provide more information on his state.
“They’ve strapped his ankle and hopefully it’s relatively minor but it’s one for the morning,” he said after the game.
England is set to face Montenegro and Kosovo in the next round of qualifiers, and Mount was expected to be named in Gareth Southgate's side.
The youngster was involved in the last round, having broken into the team in an impressive campaign so far.
He has been one of the star players for Frank Lampard's side, scoring four and providing five assists overall this campaign.
Chelsea will play Crustal Palace in the English Premier League this weekend, hoping to continue with their impressive run in recent weeks.
They are currently fourth on the table with 23 points, eight off leaders Liverpool.