Germany international Youssoufa Moukoko has been accused of lying about his age.
The Cameroon-born winger made history in the Bundesliga in 2020 when he made his professional debut for Dortmund at the age of 16, just one day after his birthday.
Moukoko is currently on loan at Ligue 1 side OGC Nice, but a new documentary coming out on Sunday called 'Tricks, Cheats, Deception - The Million Dollar Business' is claiming that the player is four years older than he portrays to be.
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The documentary claims to have the player's real name and also says that Joseph Moukoko is not the biological father, but Dortmund have now responded.
"In the case of Youssoufa Moukoko, the biological parents and the date of birth are derived from official identification documents and birth certificates issued by a German authority.
"These documents are still valid today and are the basis for playing authorizations and permits for clubs, regardless of whether they are domestic or foreign, and of course also for association teams such as the German U21 national team.
"Please 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, even to third parties through affidavits in the context of legal proceedings that the information contained in the aforementioned official documents is correct.
"This factual status is of course decisive for us, the DFB, and the player's current club."