Internacional right-back Rodinei was sent off in a remarkable turn of events that saw Flamengo take a huge step towards retaining their Brazilian league title on Sunday.
Much of the talk before the game was about Rodinei, who was only eligible for the match because a fan paid 1 million reais ($186,000) to secure his clearance to face the club who loaned him to Inter.
But Rodinei was sent off for a clumsy stamp four minutes into the second half and Flamengo took advantage, with Gabriel Barbosa getting his sixth goal in six games after 63 minutes to secure the Mengao a vital 2-1 wi
Flamengo leap-frogged Inter to lead the Brazilian Serie A standings by two points with one game left.
Flamengo play away at Sao Paulo in their final match on Thursday, while Inter are at home to Corinthians.
Inter, who would have won their first league title since 1979 with a victory over the reigning champions, went 1-0 up after 12 minutes when Edenilson scored from the penalty spot.
However, Giorgian de Arrascaeta equalised for the home side 17 minutes later when he side-footed home a cutback from Bruno Henrique.
At the other end of the table, Flamengo’s arch-rivals Vasco da Gama were almost certainly relegated to Serie B after a 0-0 draw at Corinthians.
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Bahia’s earlier 4-0 win over Fortaleza lifted them on to 41 points and out the bottom four, level on points with Fortaleza.
Vasco have 38 points but their goal difference is 12 goals inferior to their nearest rivals and so their fate was almost certainly sealed.
Coritiba and Botafogo are already down and either Bahia or Fortaleza will join them.