MADRID, Sept. 13 (Xinhua) -- Real Madrid could be without central defender Antonio Rudiger for up to three months after the German international suffered a muscle injury in training on Friday, the club confirmed.

"Following tests conducted on Toni Rudiger by the Real Madrid Medical Services, he has been diagnosed with an injury to the rectus femoris muscle in his left leg," read a statement on the club's website.

Although the club added that news of Rudiger's return was "awaiting further development," the Spanish sports papers, Diario Marca and Diario AS, both reported Rudiger will be sidelined for between 10-12 weeks.

That means he will miss around 11 games in La Liga, including the Madrid derby away to Atletico Madrid on September 27, as well as the first 'Clasico' against FC Barcelona at the end of October.

Rudiger is also out for Champions League games against Olympique Marseille, Kairat, Juventus, Liverpool and Olympiakos, leaving coach Xabi Alonso with just Dean Huijsen, Eder Militao and Raul Asensio as the only specialist central defenders in a squad that is going to be playing two games a week almost every week until the Christmas break. ■