Manchester United stopper David De Gea injured in warm-up

The Spaniard was replaced by Argentina’s Sergio Romero between the posts for the last 32 first leg in Denmark, with United’s unfamiliar defence plunged further into chaos.

Louis van Gaal was already forced to call upon youngster Donald Love – a first-time starter for United – after a spate of recent injuries. Love, 21, formed part of an unlikely back four alongside Chris Smalling, Paddy McNair and Daley Blind.

Should De Gea's complaint relegate him to the sidelines, Van Gaal would be without 13 senior players.

Wayne Rooney joined the growing list of absentees after sustaining a knee injury in Saturday’s defeat at Sunderland. The United skipper is expected to miss six weeks.