He was the 1950 FIFA World CupBrazilian coach. As a consequence of his World Cup failure, he lost his prestige among the Brazilian press and supporters of the national team. However, he was again manager of the Brazilian team in 1955 and in 1956.
From 1926 until 1936 Flávio Costa played 145 matches, mostly as midfielder, in the black and red jerseys of Flamengo and scored 15 goals in the process. From September 1934 forward he was player-manager.
Climax of his playing career was the winning of the state championship of Rio de Janeiro in 1927.