"Following tests carried out today on our player Karim Benzema by the Real Madrid medical team, he has been diagnosed with an injury to his right hamstring," the European champions said in a statement without giving a timeframe for his return.
He was injured early in the second half of Saturday's 1-0 Liga loss at Alaves in which Real conceded a late goal.
Benzema joins Marcelo, Isco and Dani Carvajal on the sidelines at the Santiago Bernabeu, with Real having gone four games without scoring in all competitions, but he should return before the Clasico against Barcelona on Oct. 28.
The 30-year-old has netted five goals this season but has failed to score in his last seven appearances.
(Reporting by Rik Sharma in Barcelona; Editing by Ken Ferris)
