Derby midfielder James Bailey is expected to be out for around three months after scans revealed his ankle injury is worse than first thought.
Bailey suffered the injury in training almost two weeks ago as the Rams prepared for their away game at Midlands rivals Coventry. X-rays have shown a small bone fracture in the 22-year-old's ankle, as well as ligament damage.
"James has a ruptured ligament and a small fracture in his talus bone in the ankle joint," Derby physio Neil Sullivan told the club's official website.
"He needs to allow the bone to heal for four weeks before he can fully bear weight again, and then the process with his rehabilitation work."
Bailey, who won the young player of the year award last season in his first year at Pride Park following his arrival from Crewe, had started Derby's opening five Championship matches this campaign prior to his injury.
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