Reece James missed training ahead of England's final group game against Panama.
The 26-year-old played the entirety of the 4-2 win against Croatia last week and Tuesday's 0-0 draw with Ghana, but per ESPN sources is dealing with a hamstring issue.
James was conspicuous by his absence from England training on Friday and is not expected to be risked as Thomas Tuchel's men attempt to wrap up top spot in Group L against Panama.
Natural back-up Tino Livramento has already withdrawn from the squad due to a calf injury and the Football Association said the Chelsea captain is "following his own programme."
James was the only member of the 26-man squad not to take part in the session at Swope Soccer Village before flying to the east coast.
Declan Rice was involved in the session having had an issue assessed in recent days, while Arsenal teammate Bukayo Saka is pushing to start having worked his way back from an Achilles problem.
England are all but assured of a place in the knockout phase but need to equal or better Ghana's result in the other Group L game to top the pool.