Anton Ferdinand was injured in England U21 win over Poland on
Tuesday evening.
He was fouled by Karol Gregorek, who was booked, and the injury could be serious.
He was replaced on 38 minutes by Leeds defender Matthew Kilgallon, who was on loan at Upton Park last season.
Meanwhile, England U17s have won the 2004 Pepsi Tournament after beating Portugal 3-1.
Hogan Ephraim finished top scorer with four goals - all of them coming in the game against Russia.