Stuart Holden's knee injury nightmare has continued with the Bolton Wanderers midfielder having undergone more surgery which could keep him out for nine months.

The United States international has played just five times in three years for Wanderers because of numerous problems with his knee, which he first injured back in March 2011 in a tackle with Manchester United's Jonny Evans.

Holden had hoped to play a part for Dougie Freedman's men down this season's stretch but he came off after just 23 minutes of a Bolton Under-21s game last Monday clutching that troublesome knee.

The 28-year-old flew back to the States and the Sky Bet Championship club have confirmed he underwent surgery on the ligaments in the knee which rules him out for at least six months.

"Unfortunately, Stuart's knee has gone," Freedman told the club's official website.

"His surgeon has had a look and has deemed this to be the best course of action.

"We're all obviously very disappointed for Stuart, but he's a warrior and a fighter and someone who knows exactly what he wants to achieve.

"Everyone at the football club is right behind him."

Holden's contract at the Reebok Stadium is up this summer but Freedman was last week adamant that, should he ever play again, he will do so in a Bolton shirt.