Now East Timor has been punished for changing the documents.
The players, who have represented clubs such as Palmeiras and Botafogo, helped the nation to its first ever win.
But now it has been banned from the 2023 AFC Asian Cup following a joint investigation by the Asian Football Confederation and Fifa.
They found the documents were doctored to falsely show the players had East Timorese heritage, with one or both of their parents being born in the country.
Three of the Brazilians played in the team's first win over Cambodia in 2012, with six playing in World Cup qualifier wins in 2015.
The AFC ruled 29 matches be forfeited, while seven matches fell under Fifa's jurisdiction.
Among the players named are defender Diogo Santos Rangel, who began his senior career at Vasco da Gama and Palmeiras. Also named is Fellipe Bertoldo, a midfielder for Botafogo in 2014, and Jaime Braganca, who has represented Portuguese club Maritimo and Bulgaria's Chernomorets Burgas.
The team, nicknamed 'the Little Samba Nation', have five wins in just under 14 years.
The 36 matches scrutinised in the investigation span a period from July 2012 to October 2015, though in a statement the AFC said it was "aware" of ineligible participation at previous events but was "unable to retrieve team line-up data for those matches".
After beating Cambodia 5-1 in 2012, East Timor overcame Laos to finish within a point of making the group stage of the AFF Championship, a tournament contested by the best nations in Southeast Asia.
However, the number of ineligible players used increased in 2015, when as many as seven were used across 10 World Cup qualifying matches where the team picked up two wins.
There is no mention in any of the reports of any player's involvement in falsifying the documents.
The East Timor Football Federation has been fined $20,000 (£16,210) with a penalty of a further $56,000 (£45,400) suspended for two years. The body's general secretary has been banned for three years.
East Timor sits north of Australia with a population of around 1.1 million people.
As a result of a small pool of players to choose from, the national team has selected nine players aged 16 or under since it was formed.
Birth and baptism certificates were doctored by football chiefs in a tiny southeast Asian country to allow a dozen Brazilians to play for them.