Madrid  - Real Madrid winger Arjen Robben will be out of action for around six weeks, the Spanish champions said Thursday.

The Dutch wideman tore fibres in his right calf while warming up for Wednesday's Champions League clash on Wednesday.

Real coach Bernd Schuster had to play Royston Drenthe down the left instead of Robben - and suffered an embarrassing 2-0 defeat.

Juventus are now four points ahead of Real in Group H, and Zenit St Petersburg are only two points behind the Spaniards.

Robben has suffered a series of muscle injuries since joining Real from Chelsea in July 2007. He is Real's only genuine winger, since Robinho left for Manchester City in August.

Defenders Sergio Ramos and Pepe, meanwhile, are doubtful for Real's home game against Malaga with minor injuries.

Real are currently third in La Liga, two points behind leaders Barcelona. Anything less than a convincing defeat of Malaga will increase the pressure on the embattled Schuster. (dpa)