Derby forward Tomasz Cywka is to see a specialist about his knee injury.
The 22-year-old suffered ligament damage during the second half of the goalless draw at home to Barnsley earlier this month.
He missed the defeat at Middlesbrough, the victory over Swansea and is also out of the trip to Crystal Palace on Saturday.
Cywka underwent scans last week and began his rehabilitation but still has some discomfort in his knee.
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