Mário de Castro was the first Atlético Mineiro player to be called up for the Brazil national football team, and scored 195 goals in 100 matches for the club.

Mário was the first Atlético Mineiro player and first outside of Rio de Janeiro or São Paulo to be called up for the Brazil national football team.

In 1929, the inauguration of Atlético's Antônio Carlos stadium had the presence of Horácio Werner, a CBD official, and Alysio Távora, a journalist from Rio de Janeiro.

However, he was to serve as backup for Botafogo's Carvalho Leite, so the call-up was refused, as Mário de Castro wanted to play in the first squad.

Celebrations over the victory became tragical, however, as a Villa Nova fan was shot and killed by an Atlético director, a fact which outraged Mário de Castro and prompted him to end his career at 26 years old.