Keogh was sacked for his involvement in a crash in September that led to team-mates Tom Lawrence and Mason Bennett pleading guilty to drink-driving.

The 33-year-old sustained knee ligament damage and could be out for 15 months.

Keogh was given 14 days to appeal against the club's decision.

The Republic of Ireland international's injury could mean he is not fit to play again until December 2020, six months before what would have been the end of his contract with the Championship side.

BBC Derby Sport understands that Keogh turned down an offer of a revised deal on reduced wages, but is now considering fighting the decision to sack him.

Manager Phillip Cocu, speaking at a news conference prior to Saturday's game against Hull City, said it was a "club decision".

"It's very complicated," Cocu added. "I think for everybody it's a difficult and hard situation. At the moment I cannot go into the matter, it's still ongoing."

The Rams said in a statement on Tuesday that they "will not tolerate any of its players or staff behaving in a manner which puts themselves, their colleagues, and members of the general public at risk of injury or worse, or which brings the club into disrepute".

Lawrence and Bennett were fined fined six weeks' wages by the club following the 24 September crash, while Derby Magistrates' Court ordered the players to carry out 180 hours of unpaid work, gave them a 12-month community order and banned them from driving for two years.

Analysis

BBC Radio Derby's Chris Coles

Understandably there's been lots of conjecture following the sacking of Richard Keogh - with many questioning why the club captain has been sacked, yet Mason Bennett and Tom Lawrence have kept their jobs.

It's understood several factors counted against Keogh. He was the club captain, a senior player and it was felt he should have taken more responsibility on the night in question. These reasons, coupled with a serious injury sustained through a non-football activity, are why the club have felt it necessary to terminate Keogh's contract.

We almost certainly haven't heard the last of this, with Keogh expected to appeal against the decision.