Madrid says Pepe injured a muscle in his right leg during its 1-0 loss at Bayern Munich in a friendly on Wednesday.
Madrid was also missing stars Cristiano Ronaldo and Karim Benzema for that preseason match.
Ronaldo is expected to recover from back pain soon, but a right thigh injury has left Benzema also in doubt for the Spanish league opener on Aug. 23 at promoted club Sporting Gijon.
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