Leeds suffered another injury blow during a friendly match against Elche.
The Premier League club are working hard to prepare for the resumption of the domestic season.
However, they have been rocked by news that Crysencio Summerville hobbled off during the match.
The Dutch youngster, who scored in four successive Premier League games prior to the World Cup break, suffered a hard tackle during training in Spain before the game as well.
He then came off in the 11th minute of the friendly after a tackle from Elche defender John Donald.
Per the Daily Mail, Leeds boss Jesse Marsch will have to wait for scans to learn the full extent of the issue.
Forward Patrick Bamford is also out for three more weeks after groin surgery.