The Arsenal midfielder limped off in the 63rd minute of the international friendly at Sun Life Stadium in Miami on Wednesday as England were tested by a resilient Ecuador side.
Goals from Wayne Rooney and Rickie Lambert appeared to have given England victory after Enner Valencia had put the South Americans ahead early on.
However, Michael Arroyo earned a draw for Ecuador seven minutes after Oxlade-Chamberlain left the field, before both sides were reduced to 10 men as Raheem Sterling and Antonio Valencia were dismissed following a heated exchange.
But the main concern for England surrounds Oxlade-Chamberlain after manager Roy Hodgson revealed that the 20-year-old is set to undergo a scan on the injury.
"We fear there may be ligament damage to Alex Oxlade-Chamberlain," Hodgson said.
"He needs a scan on the injury."
