The 25-year-old Girona midfielder had been in excellent form during the group stage of the competition but played no part in Sunday's 1-0 win over Tanzania in the last 16 in Rabat.
He was pictured arriving at the stadium in the Moroccan capital using crutches and wearing a medical boot on his left foot as Bilal El Khannouss took his place in midfield.
"He has a tear in his calf and can't play at the AFCON. He is unavailable for five to six weeks," Morocco coach Walid Regragui confirmed after the game against Tanzania.
"He injured himself in training yesterday. It is an old injury that he had with Girona and the scar has opened up again."
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