England star Declan Rice was absent from training on Wednesday due to illness.
The West Ham midfielder has started every game for the Three Lions at the World Cup so far.
Gareth Southgate’s side face their biggest test yet when they take on France in the quarter-finals on Saturday – live on talkSPORT.
Twenty-two England players trained in Qatar on Wednesday, with striker Callum Wilson also out as he continues rehabilitation for a minor strain.
Meanwhile, there have been no updates on Raheem Sterling, who was forced to return home on Sunday due to a break-in at his family home.
If fit, Rice is a guaranteed starter for the France showdown, and his sudden illness will cause concern, with the game just three days away.
The 23-year-old played alongside his midfield partner Jude Bellingham, who is winning all the accolades in Qatar.
Earlier today, England legend Stuart Pearce told talkSPORT that Rice would be a key weapon in helping Southgate stop Frenchman Kylian Mbappe.
The former West Ham assistant explained how the midfielder is often used to help double attackers with his full-back.
Rice’s influence in this England team cannot be underestimated: he covered more distance than any other player in Sunday’s 3-0 win over Senegal.
Three Lions right-back Kyle Walker will need all the help he can get to deal with Mbappe, the tournament’s top scorer and arguably the best player in world football in his current form.
However, the Blues have their own worries, with Mbappe missing training on Tuesday and spending the session in the recovery room.
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