Taça Guanabara is the first stage of the competition, with the teams divided into two groups. The traditional "big four", namely, Botafogo, Flamengo, Fluminense and Vasco da Gama are seeded—two teams of the "big four" put into each group. It is possible other teams also be seeded in some ways, but the seeding criteria is not codified in the regulation and has never been publicly available. The teams play one match with each team in their group. The top team in each group plays the second team in the semi-finals; the winners qualify for the final match.