Sunderland manager Martin O'Neill has claimed that frontman Nicklas Bendtner could be sidelined for a long-term spell after suffering facial injuries.

It was expected that the former Arsenal striker would be out of action for some time after breaking his nose during the Black Cats' 2-0 win over Swansea City on Saturday.

"[Bendtner's] got a bit more than a broken nose," O'Neill told the Sunderland Echo. "It's difficult to put a timescale on it, but it's going to be lengthy. We thought at one stage he might be okay. The early signs, even on Sunday morning, were that it looked as if it might be okay.

"But he's going to be out for a number of weeks now, which is definitely a blow to us. He has a few cracks and we just have to bide our time with that.

"That's a big blow to us and to the lad himself, who was beginning to enjoy a decent spell of football for us."

Sunderland will definitely be without the 24-year-old for their FA Cup fourth-round match against Middlesbrough on Sunday.