Manchester United goalkeeper Ben Foster faces an extended period out of the game as he prepares to undergo knee surgery.

The 24-year-old, who spent last season on loan at Watford, began suffering knee trouble towards the end of the campaign.

He was then assessed by medical staff at England and United in May after he reported for international duty.

A United spokesperson said: "Ben Foster has a cruciate ligament injury in his right knee and will require an operation in two to three weeks' time."