Derby have been hit with a £50,000 fine by the Football Association for "failing to control their players".
The Rams denied the charge, which related to a melee during the Coca-Cola Championship encounter against Swansea at Pride Park on February 20, but were found guilty at a disciplinary hearing.
Swansea were fined £15,000 for a similar charge, £7,500 of which was suspended.
It takes Derby's total of FA fines for this season to £115,000 as they had already been fined £65,000 for failing to control their players in two matches against rivals Nottingham Forest.
The Commission chairman stated: "The Commission was deeply concerned that this was the third occasion in a period of eight months that Derby County FC have been charged with a similar offence.
"Furthermore, the Commission felt the incident could have easily been avoided by stronger restraint from players from both clubs."
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