Feyenoord are set to be without captain Theo Lucius for the majority of the remainder of the season.
The midfielder limped out of Sunday's draw with Willem II shortly before the half-hour mark having picked up a leg injury.
The club sent Lucius for a scan and the results showed a tear to his hamstring.
Feyenoord's medical team have informed Lucius that he will be out of action for six weeks, which would see him sidelined until the start of May.
The Kuip club are still pushing to claim a place in Europe and the loss of Lucius will be a blow to coach Erwin Koeman.