It was an unusual rags-to-riches story when Bakery Jatta, a then-teenage refugee with no professional experience, signed a contract with former European champions Hamburg SV back in 2016.
But local authorities in Hamburg are now reviewing his passport details following media reports he maybe two years older than initially stated, he may have changed his name and also may have played for professional teams in Africa.
Second division`s Hamburg have stood by the player, saying he has had a valid passport and a player licence for three years.
"We expect from the league and the football association a clear and swift positioning. At the end of the day, our player has had a valid passport for three years as well as licence," Hamburg sports director Jonas Boldt said in a club statement late on Thursday.
"It is unacceptable to us that his right to play is questioned by such assumptions."
The German FA said this week it had asked Hamburg for details and would make a decision in "due course."
Gambia-born Jatta had arrived in Germany in 2015, signing his deal in 2016 and being hailed as a shining example of integration amid a then ongoing refugee crisis in Europe.
Jatta was thrust into the spotlight when Nuremberg appealed Monday`s 4-0 defeat hours after media reports on the player`s personal details.
"We are fully behind Bakery and will continue to fully plan with him for training and matches as he is a completely integrated colleague and valuable player," Boldt said.
Hamburg`s municipal authority has said it is looking into the matter.
Under German law falsifying documents could lead to the person`s residency status and/or work permit in Germany to be revoked and in some cases carry prison sentences.