Real Madrid have confirmed the injury to their Spain defender Sergio Ramos. AP Photo/Antonio Calanni

Real Madrid have confirmed that captain Sergio Ramos suffered a knee ligament strain in Spain's win over Albania on Sunday, meaning the Blancos captain is likely to be sidelined for around a month.

Ramos was taken off in the 80th minute of the World Cup qualifier in Shkoder after falling awkwardly on his left knee as he took part in an attack.

He underwent tests on his return to the Spanish capital, with Madrid confirming the injury in a statement.

"After tests carried out today on our player Sergio Ramos, he has been diagnosed with a grade 2 sprain of the medial collateral knee ligament in the left knee," the statement said.

"His recovery will continue to be assessed."

While Madrid did not mention any likely recovery period Ramos could miss as many as six games, including the two Champions League fixtures against Legia Warsaw and a league clash with Athletic Bilbao.

However, it is hoped he will be back for the derbi at Atletico Madrid on Nov. 19.

Madrid coach Zinedine Zidane is also without midfielders Luka Modric and Casemiro, while James Rodriguez's recovery from a calf muscle strain was complicated by his travelling to Colombia during the international break.

However, left-back Marcelo remains on track to make his comeback in Saturday's La Liga game at Real Betis.