England captain Wayne Rooney and defender Ryan Bertrand missed training on the eve of Tuesday’s friendly against 2010 world champions Spain at Wembley.
Manchester United striker Rooney and Southampton left back Bertrand were forced out of the session by “minor issues”, the England team’s official Twitter feed said on Monday.
With only 19 outfield players training, 17-year-old Tottenham Hotspur midfielder Dylan Duncan was invited to join in.
England defeated bitter rivals Scotland 3-0 in a World Cup Group F qualifier on Friday while Spain crushed Macedonia 4-0 in Group G on Saturday.
Tuesday’s game will be the last of Gareth Southgate’s four-match audition as England interim manager.
The former Under-21 coach landed the role on a temporary basis after Sam Allardyce was sacked in September for behaving “inappropriately” when seeking a lucrative sideline role while talking to undercover reporters.