Douglas Costa revealed that he and his Gremio teammates felt compelled to throw a game against Flamengo in 2009 out of fear for their lives.
Speaking to YouTube channel Pilhado, the 27-year-old, now with Juventus, said the defeat saved his life because it prevented their club's arch-rivals Internacional from winning the title.
"It was 1-1 at the end of the first half and we were playing with a reserve team," Costa said. "In the second half, we received news that if the result stayed that way, Internacional would have won the Brasileirao.
"The game ended 2-1 for Flamengo and everything worked out fine. We made changes and I would dribble from one side to the other, where I could do no harm. I couldn't play as I am capable of and it was horrible -- but I had to play to avoid winning."
Costa said Gremio directors entered the dressing room at half-time -- something Costa, who left in 2010, considered "standard procedure" in Brazil -- and told them "it was up to us what we did, but that the responsibility would be ours."
He added: "They said if we had won, the Gremio fans would have run on to the airport runway and not let us leave."
Luiz Onofre Meira, Gremio's vice president at the time, denied Costa's claim. Speaking to Zero Hora, he said neither he nor club president Duda Kroeff entered the dressing room during that game and said that the team "did everything the right way."
"There were not any orders from [the board]," Meira told Zero Hora. "They played and did the best they could. They did very well, indeed, as they were able to hold a 1-0 win almost until the end. However, Flamengo was the better team that day. They were very superior."