Chelsea defender Levi Colwill has suffered an agonising ACL injury.
The club have confirmed that the defender has undergone successful surgery.
It is understood the injury was non contact and happened on Monday, the first day back from training after the three weeks off after the Club World Cup Final.
Colwill is expected to be out for the majority of next season and it remains to be seen whether or not Chelsea add a new defender or trust within.