Madrid, Spain (SportsNetwork.com) - Real Madrid defender Sergio Ramos will spend the next five weeks on the sidelines because of a hamstring injury.

Ramos left Wednesday's 2-1 win over Sevilla after picking up the problem, and tests have revealed that the Spain international has suffered a torn hamstring, ruling him out of this weekend's Madrid derby against Atletico.

The 28-year-old Ramos has started 18 games in La Liga, scoring three goals for Madrid, which sits four points clear of second-place Barcelona entering the weekend.

Ramos becomes the latest injury casualty for manager Carlo Ancelotti, who will also be without James Rodriguez, Luka Modric and Pepe for Saturday's match.

It was also confirmed on Friday that defender Marcelo will miss out on the Atletico match due to suspension because of an accumulation of yellow cards.

However, Ancelotti will have the services of star forward Cristiano Ronaldo as the Portugal international will return to the team after serving a two-game ban.