Richard Keogh has formally appealed against Derby County's decision to sack him.
Keogh was dismissed by Nottingham Forest's arch-rivals on grounds of gross misconduct at the end of last month, and his contract terminated with immediate effect.
The Republic of Ireland international was given 14 days to appeal against the decision.
As expected, the central defender has now taken up that option, Derbyshire Live understands.
Keogh is facing at least a year out of action after sustaining a serious knee injury in a car crash that resulted in Rams team-mates Tom Lawrence and Mason Bennett being convicted of drink-driving.
Lawrence and Bennett were punished in the courts and fined by their club - but remain on the books.
Keogh has the backing of the Professional Footballers' Association (PFA) and will fight his dismissal.
The Rams will now take time to consider his appeal.
