Derby boss Paul Jewell has not ruled out the prospect of midfielder Giles Barnes requiring a second knee operation.

Barnes was forced to see renowned specialist Dr Richard Steadman in Colorado last week for initial surgery on his kneecap.

The 19-year-old midfielder, who is not expected to return until the start of next season at the earliest, is now undergoing rehabilitation in the United States.

However, it has yet to be determined whether the operation last week was a complete success.

"I think Giles is coming back next Tuesday but we are really pleased with the outcome of the operation," said Jewell in the Derby Evening Telegraph.

"He will have to go back but whether he needs a second operation we don't quite know yet."