Real Madrid's Argentine midfielder Gago will be sidelined for at least a month through injury, the club announced on Wednesday.

Gago suffered a "sprain to the internal lateral ligament of his left knee", it said in a statement.

He joins Pepe, Ezequiel Garay, Raul Albiol and Brazilian midfield star Kaka on Real's injured list ahead of the start of the Spanish league season this weekend.