The Moroccan forward sustained the injury during the clash with Spakewnburg and missed the Eredivisie game against Groningen on Saturday.
El Hamdaoui underwent an MRI scan on Monday that indicated that the 25-year-old has torn a muscle in his left leg.
The highly rated forward will miss the games against Feyenoord, VVV and Roda, as well as Champions League games against Arsenal and Olympiacos.
