Miami: England winger Alex Oxlade-Chamberlain has a "medial knee ligament" injury, the Football Assocation said in a statement on Thursday which leaves the player's participation in the World Cup in doubt.
Oxlade-Chamberlain picked up the injury during Wednesday's 2-2 draw with Ecuador in Miami and the FA said the England medical team were "continuing to monitor and treat the injury".
Media reports said the recovery time for the Arsenal winger could be anything from 10 days to three weeks which would leave England manager Roy Hodgson with a tricky decision to make over whether or not to replace the 20-year-old or take him to Brazil and hope he recovers to play a role.
England face Honduras on Saturday, also at Miami's SunLife Stadium, their final warm-up game before their June 14th meeting with Italy in Manaus.
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