Vitesse coach Leonid Slutsky admits Charly Musonda is still carrying a knee injury.
That setback occurred in September last year. In his first game for Vitesse, a friendly against Royal Antwerp, the Belgian suffered a cruciate ligament injury. In consultation with Chelsea's medical staff, it was decided not to operate. With strength and stability exercises, Musonda was able to eventually return to Vitesse at the end of last season.
But now he has suffered a fresh blow.
“We wanted to use him for an hour. It was too early for ninety minutes. But the old injury plays out. This is a chronic injury.
"It is difficult to return to the level after so much injury."
The alarm bells were ringing during a training session last week, with Musonda complaining of a knee strain.
Musonda is now returning to Chelsea for a new medical check. It's Blues policy that any player away on-loan whom suffers an injury is to immediately return to Cobham for Chelsea's medical chiefs to run tests.
Slutsky admits losing Musonda is a blow, though concedes it's a situation which hasn't surprised him.
“We now have to wait," he continued. "I am in no way shocked. The concerns have been around for some time.
"The injury has been going on for some time."
Sunday's game at Heracles Almelo 1-1.
- updated August 26