Alleged fake identities and an apparent cover-up could cause huge problems with just weeks to go before the first match.
Ecuador are in hot water and face the possibility of being kicked out of the World Cup in Qatar after audio and documents claim to prove right back Byron Castillo admitted to using a false birth certificate.
After Ecuador qualified for the World Cup finals, the Chilean FA lodged an official complaint to FIFA in April and claimed that Castillo falsified his birth documents and was an illegal immigrant.
They claim to have proof that Castillo was actually born in Tumaco, Colombia in 1995, and not in the Ecuadorian city of General Villamil Playas in 1998, which is what his official documents say.
FIFA looked into the matter and dismissed the case from Chile and ruled that Castillo is from Ecuador.
However, the Daily Mail have now published a detailed report which appears to prove that Castillo is Colombian and the whole thing was covered up.
According to an audio recording of an interview Castillo gave to investigators four years ago, he admits the following:
Clearly states he was born in 1995 as opposed to the 1998 date given on his Ecuadorian birth certificate.
Gives his full name as Bayron Javier Castillo Segura, matching the details of his Colombian birth certificate, rather than the name on the Ecuador certificate, Byron David Castillo Segura.
Describes in detail leaving the Colombian city of Tumaco for San Lorenzo in Ecuador to pursue a career in football.
Names an Ecuadorian businessman who provided him with a new identity.
The recording comes from a formal interview conducted by the head of the Ecuador Football Federation's Investigative Commission with Castillo in 2018.
Hosts Qatar are due to play Ecuador in the opening game of the World Cup against on 20 November so removing them from the tournament at this late stage would be a major embarrassment for FIFA. If that decision is made then Chile would take Ecuador's spot this winter.