Knol still struggling
By Jeffrey Glorie
Last Updated: 01/01/70 1:00am
The defender has been sidelined for over a year with the problem, but returned to training earlier in the summer.
However, he has been forced to put his rehabilitation programme on hold after complaining of pain in the joint.
"I keep getting moisture in the knee after three days of training," the 22-year old told RTV Gelderland. "This is very annoying."
Knol has long been viewed as one of Holland's brightest defensive prospects, and his continued injury troubles will be a real worry to Vitesse.