The player's father, Joseph, has been quoted stating Youssouf is four years older than his official 20 years of age.
Moukoko is currently on-loan with Manchester United's French partners, Nice, which have a permanent option included in the deal.
Responding to the claims, BVB stated: “In the case of Youssoufa Moukoko, the biological parents and dates of birth are derived from official identification documents and birth certificates issued by a German authority. These documents are valid to this day and are the basis for playing rights and permits for clubs, whether at home or abroad, and of course for association teams such as the German U21 national team.
"Also note that both the player and the biological parents identified in the above-mentioned documents have declared to us and, in the case of the parents, also to third parties, through affidavits during legal proceedings, that the information in the above-mentioned official documents is correct. This condition is of course crucial for us, the DFB and the player's current club."
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