American midfielder Stuart Holden has undergone another operation to repair ligaments in his right knee and will be sidelined for six to nine months.

American midfielder Stuart Holden has undergone another operation to repair ligaments in his right knee and will be sidelined for six to nine months.

Bolton, Holden's club in England's second-tier League Championship, made the announcement Tuesday, eight days after the 28-year-old lasted less than a half-hour with the Bolton under-21 team against Everton. That was his first match since tearing his right anterior cruciate ligament during the United States' 1-0 victory over Panama in the CONCACAF Gold Cup final on July 28.

"Unfortunately, Stuart's knee has gone. His surgeon has had a look and has deemed this to be the best course of action," Bolton manager Dougie Freedman said. "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 posted a letter from a fan on his Facebook page in which a mother whose 17-year-old son tore an ACL said her son had looked to Holden as inspiration for his own recovery.

"This is why I continue to fight and never give up," Holden wrote. "An email from a fan that brought tears to my eyes and strength to my heart. No matter what obstacles are thrown in front of me, I will conquer them."