Nottingham Forest midfielder Andy Reid could be out of action until January.
The 32-year-old hurt his groin in the derby against Derby County in September and a scan has revealed the damage is more serious than first feared.
Reid has said the best-case scenario could see him return in eight weeks, but it could be as long as 12 weeks.
"I'm gutted but all I can do now is be as positive as I can and work as hard as I can to come back stronger," he told the Nottingham Evening Post.
Earlier this week Reds defender Jack Hobbs was ruled out until Christmas because of an ankle injury.