Adrian Mutu's appeal against an order to pay former club Chelsea €17.17million (£14.7m) in damages has been rejected by the Court of Arbitration for Sport.
The Romania international, who is now at Fiorentina, was ordered to pay the sum by Fifa last year after he was fired by the Blues in 2004 for testing positive for cocaine.
Mutu appealed against the ruling, claiming the amount of money was not justified, but that has been rejected.
A statement said: "The Court of Arbitration for Sport (CAS) has dismissed the appeal filed by the Romanian football player, Adrian Mutu, against the decision rendered by the Fifa Dispute Resolution Chamber (DRC) on 7th May 2008 in which he was ordered to pay €17,173,990 in compensation to his former club, Chelsea FC, for breach of contract."
Chelsea terminated Mutu's contract in October 2004, one year after he had joined the Premier League side from Parma.
Since leaving Chelsea, the 30-year-old has rebuilt his career, first at Juventus, who he signed for in 2005 despite serving a seven-month ban for the cocaine offence, and since 2006 at Fiorentina.