Newcastle boss Steve McClaren admits striker Emmanuel Riviere may require surgery on his injured knee.

The Frenchman was left out of the Magpies' season-opening draw against Southampton on Sunday because of the injury and McClaren concedes the 25-year-old may need an operation.

"I think Manu Riviere's knee was painful after training so he might have to have surgery," McClaren told the Newcastle Evening Chronicle.

"We are investigating that."