The French international picked up the problem early on in the Clasico defeat on December 23, and an MRI scan on Saturday confirmed the injury.
Following tests carried out on Karim Benzema by the Sanitas Real Madid Medical Services, he has been diagnosed with a muscular injury in biceps femoris of his right leg. His recovery will continue to be assessed.
The injury comes amidst a five-game goal drought in all competitions, including the Club World Cup for the striker. He last scored on Nov. 25 and has only two La Liga goals all season.
Real Madrid had to reschedule some games due to participating in the FIFA World Club Cup, and as a result, the Spanish, European and World Champions are facing fixture congestion with six games scheduled in January.
Benzema is expected to miss the Copa del Rey double-header with Numancia, a La Liga clash with Celta Vigo and maybe even the games with Villarreal and Deportivo La Coruna.
Most fans have been wanting to see the team without Benzema for a while so it will be interesting to see if Real Madrid are actually a better side without him or not.
Gareth Bale is finally completely healthy and Zidane is expected to start him upfront alongside Cristiano Ronaldo with Isco playing behind them.
With Real Madrid being linked with summer moves for Harry Kane, Robert Lewandowski and Mauro Icardi it is clear that Zidane wants more production from his No 9. Which raises an interesting question. Have we seen the last of Karim Benzema being an automatic starter in the Real Madrid line-up?