League leaders AZ Alkmaar have lost Gijs Luirink after he sustained a broken cheekbone at home to FC Twente on Sunday.
He collided with opposition midfielder Otman Bakkal in the 2-2 draw and is now expected to undergo reparatory surgery.
It is not yet clear how long he will be out, but team-mate Danny Koevermans is expected to return after his aerial collision with the visitors' Ramon Zomer in the same game.
"I have two gashes above my eyebrow and three stitches," explained Koevermans.
"After the aerial challenge I blacked out for a moment, but after that I was okay again. I don't think it's that bad."
The Eredivisie leaders will hope to continue their fine form so far this season in their next match away at third in the league Roda JC Kerkrade on Sunday.