AC Milan midfielder Alexander Merkel will be out of action for at least two months with a knee injury, the club have confirmed. Merkel was hurt in training last week and tests done on the 19-year-old revealed ligament damage on his right knee. A statement from AC Milan read: \"If there are no complications, Merkel will be available to play in eight weeks.\" Merkel\'s injury is a setback for Milan boss Massimiliano Allegri. The Germany U-20 player only returned to Milan in joint ownership from Genoa earlier this month as i Rossoneri were keen to strengthen their midfield line after losing Mathieu Flamini, Gennaro Gattuso and Alberto Aquilani to injury.