Derby County midfielder Joe Ledley has undergone a small procedure on his hip.
Ledley, 31, will now begin his rehabilitation programme with Derby’s medical staff.
The Wales international has made four appearances for the Rams so far this season and found the net in the 2-0 home victory over Ipswich Town in August.
Ledley has appeared 30 times in a Derby shirt since arriving at Pride Park Stadium just over a year ago.
Meanwhile, tickets for the trip to Stamford Bridge to take on Chelsea in the fourth round of the Carabao Cup are now on sale to away members and season ticket holders who have attended two or more away games this season, excluding pre-season fixtures.
The game, which takes place on Wednesday 31st Octobe, October 31 (7.45pm kick off), will be broadcast live on Sky Sports.
Derby secured their passage through to this round of the competition with away victories at Oldham Athletic, Hull City and Manchester United.
The Rams have been allocated 4,082 tickets for the game.
Tickets cost £25 for adults, £12 for seniors and £12 for U20s (aged 2-19), with under-13s needing to be accompanied by an adult aged 18 or above.