Sunderland boss Gus Poyet has revealed that defender Patrick van Aanholt will be out of action for up to three months with a shoulder injury.

The 24-year-old dislocated his shoulder in his side's win over Crystal Palace last week, and missed the Black Cats' 1-1 draw with Everton on Sunday.

Poyet has admitted that the left-back will require an operation on the problem, and as a result will be unable to play until January at the earliest.

"Unfortunately Patrick is going to need an operation which means he is going to be out for two and a half to three months,"' Poyet told the club's official website.

"It is a big loss because he is a left-footed left-back and there are not too many of them in the world, but we will help him and we will have to cope with it.

"I am really looking forward to seeing a few players back within the international break."

Sunderland are 14th in the Premier League following their draw against the Toffees.