MADRID, Jan. 7 (Xinhua) -- Real Madrid's injury crisis deepened on Monday with the confirmation that they will be without German international midfielder Tony Kroos for the rest of the month.

The club confirmed on its official website that Kroos has suffered a 'Grade 2' strain on the left side of his groin. Although the club say his return "depends on how the injury evolves", that kind of injury usually sidelines a player for at least 3 weeks.

Kroos will miss his side's two Copa del Rey games against Leganes, as well as next weekend's difficult Liga Santander game away to Betis, further league matches against Sevilla and Espanyol and the quarter-final games in the Cup if Madrid get past Leganes.

The German picked up his injury during Sunday's 2-0 defeat at home to Real Sociedad which leaves Real Madrid fifth in the league standings, 10 points behind leaders FC Barcelona. Santiago Solari needs better results to keep his job.

However, with Kroos joining Gareth Bale, Marcos Llorente and Marco Asensio on the injury list, Solari is running out of options.