The basis of this study was the decisions of the FIFA Dispute Resolution Chamber, which were appealed to the Court of Arbitration for Sport (CAS) on the subject of proving the status of a football player, which affects the obligation of clubs to compensate for the preparation and training of players, payments under the solidarity mechanism; the influence of the labor nature or civil law nature of the contract with a football player on his status as a professional athlete; differentiation of a professional contract, an amateur contract and other contracts with a football player in terms of impact on the status of a professional athlete; distribution of responsibilities between the national association of a member of FIFA and the football club to ensure the accuracy of the information in the passport of a professional football player and some other problematic issues