Cardiff City must pay Nantes the first instalment of the transfer fee agreed for Emiliano Sala before the Argentine striker's death, the Court of Arbitration for Sport (CAS) said on Friday after dismissing an appeal from the Championship club.
Sala's plane crashed in the English Channel, killing him and the pilot, as he travelled to Cardiff after signing for €17 million in January 2019 from the French side.
The body of the 28-year-old was recovered nearly three weeks later after an underwater search found the wreckage.
Cardiff had appealed against a FIFA decision ordering them to pay the first instalment of his transfer fee which amounted to €6m.
"The challenged decision, in which Cardiff City was ordered to pay €6m to FC Nantes in connection with the transfer of the player Emiliano Sala between the clubs, is confirmed," CAS said in a statement.
"The CAS Panel found the player's transfer from Nantes to Cardiff City to have been completed.
"Because the conditions set out in the Transfer Agreement were fulfilled prior to the player's death, Nantes' claim for the first instalment of the transfer fee was upheld."
Nantes welcomed the decision, saying they were "delighted" the years-long procedure was finally over.
The CAS added that the proceedings only concerned the first instalment of the transfer fee out of the total €17m agreed.
"The other instalments were not due at the time of the procedure before the FIFA instances," CAS added.
"The CAS Panel also confirmed that it was not for FIFA to entertain the claim of Cardiff City that it was not required to pay any transfer fee to Nantes."