The Court of Arbitration said the club should pay what the player would have received after tax and other deductions.
Juventus have been ordered to pay Cristiano Ronaldo £8.3m wages owed the player.
The order was given by an Italian court.
Ronaldo, 39, agreed to defer wages when football in Italy was halted by the COVID-19 pandemic in the 2020-21 season.
The Portuguese had claimed he was owed more than £17m by his former club.
The Court of Arbitration said the club should pay what the player would have received after tax and other deductions.
Ronaldo spent three seasons in Italy with Juventus between 2018 and 2021, helping them win two Serie A titles.
He left for his second spell with Manchester United and after 16 months at Old Trafford, joined Saudi club – Al-Nassr.
The five-time Ballon d’Or winner – awarded to the world’s best player – was ranked by American business magazine Forbes as the world’s highest-paid sportsman in 2023, with earnings of £109m.