At the beginning of the First World War, he volunteered as a soldier of the Royal Serbian Army.
After the Football Association of Yugoslavia moved from Zagreb to Belgrade in 1930, he was elected secretary for foreign affairs.
Until the end of his life, he wrote interesting and above all useful articles in the field of medicine in Nedeljna Borba.
He wrote a memoir entitled Dugo putovanje kroz fudbal i medicinu (A long journey through football and medicine).
According to his son, Andrejević injected chocolate into the veins of Yugoslav footballers at halftime of a deciding 1974 FIFA World Cup qualifier where Josip Katalinski scored the winning goal which sent Yugoslavia to the World Cup.