A deal between Malky Mackay and Crystal Palace has reportedly fallen through after Cardiff City submitted a dossier to the Football Association questioning his conduct with the club.

Mackay, who has strenuously denied any wrongdoing, had been offered a three year contract and a way back into football following his sacking by Cardiff last December. Mackay appeared poised to replace Tony Pulis as manager.

Mirror Sport understands the dossier also names Palace director of football Iain Moody who worked with Mackay at Cardiff.

Cardiff have questioned the level of fees, commission and role of agents in several deals during Mackay’s two years at the club, which the team won promotion to the top flight for the first time since 1962.

In the bitter fall-out from his sacking Mackay launched a £7.5million legal claim against the club.

Palace were fined £10,000 by the Premier League last week after it was alleged that Moody got the Cardiff line-up before they played his former club last season in a vital relegation match.