Atlético Mineiro–Flamengo rivalry

The Atlético Mineiro–Flamengo rivalry is a high-profile inter-state rivalry between Brazilian professional football clubs Atlético Mineiro and Flamengo. The clubs first played against each other in 1929, but until regular competitions were introduced in Brazilian football in 1959, the encounters were played at friendly level, since they come from different states: Flamengo is from Rio de Janeiro, while Atlético Mineiro hails from Minas Gerais.

Source: Wikipedia — Atlético Mineiro–Flamengo rivalry (CC BY-SA 4.0)