David Silva: Manchester City playmaker ruled out for up to a month and will miss Manchester United clash

Silva suffered a knee injury against Newcastle on Wednesday

David Silva is forced to limp off against Newcastle (AP)

Manchester City's David Silva has been ruled out for three to four months with a knee injury, meaning he will miss this weekend's crucial derby against Manchester United at the Etihad Stadium.

Silva suffered the injury in City's 2-0 League Cup defeat by Newcastle on Wednesday night, when he was forced off in the ninth minute.

The Spain playmaker had a scan on his knee yesterday which showed ligament damage.

In addition to the United tie, Silva will also miss the Champions League matches against CSKA Moscow and potentially Bayern Munich too at the end of next month.

City manager Manuel Pellegrini said today: "David is a very important player but we have a squad and we will have to replace him with another player."

City manager Manuel Pellegrini said today: "David is a very important player but we have a squad and we will have to replace him with another player."