Fiorentina goalkeeper Sebastien Frey has undergone surgery on the serious knee injury that has ruled him out until the spring.

The 30-year-old, who damaged his anterior cruciate ligament in training last week, will leave hospital tomorrow to begin a five-month rehabilitation period.

"Fiorentina announces that Sebastien Frey has undergone an operation for anterior cruciate ligament reconstruction performed by Professor Cerulli," read a statement on the club's website.

"The player will be discharged from the hospital tomorrow to start rehabilitation in Florence."

Former Celtic goalkeeper Artur Boruc has taken Frey's place in Fiorentina's starting XI, and made his first Serie A appearance in La Viola's 1-0 win over Chievo at the weekend.

Frey's absence is a further blow to Fiorentina, who are already without star striker Steven Jovetic for six months.

Midfielder Riccardo Montolivo joined the club's growing injury list yesterday when he was ruled out for up to six weeks after surgery on an ankle injury.