The first of just three Afro-Argentine players to represent their country, alongside Juan Manuel Ramos Delgado and Héctor Baley, De los Santos was born on 17 May 1902 in the city of Paraná, near the Uruguay border.
His parents originated from Angola, speaking Portuguese at home, the language of his antecedents. After the premature death of his parents, De los Santos moved to Buenos Aires, where he came to the notice of Third Division club Oriente del Sud. His performances for Oriente earned him a transfer to San Lorenzo in the top-flight.
De los Santos made his First Division debut for the club five days after his 19th birthday, scoring against Banfield.
However, he failed to establish himself at San Lorenzo, moving on to Sportivo Dock Sud in 1921, where De los Santos earned the first of his five caps for Argentina a year later.
It was after transferring to El Porvenir in 1924 that his career hit the heights, scoring 80 goals in 148 games over the next seven years, becoming a club legend in the process.
In 1925, De los Santos helped his country win the South American Championship on home soil, but it was to be the last time that he pulled on the famous Albiceleste jersey.
Despite being in the form of his career, De los Santos was overlooked for the 1930 World Cup. Some have later claimed that this was due to the colour of his skin.
Although no definitive evidence exists, it is true that such a move would have reflected prevailing racial attitudes.
While neighbouring Uruguay embraced the selection of black players for its national team, Argentine footballers were almost exclusively white.
With the introduction of professionalism in 1931, De los Santos moved to one of Argentina’s biggest clubs, Huracán, where he spent three years, before retiring to become a customs officer at the port of Buenos Aires.
However, such was the impression that De los Santos made at the Parque Patricios club, he was three times tempted back to the club as coach in 1935, 1940 and 1945, as Huracán tried to recapture their past glories of the amateur era.
De los Santos died on 16 February 1982. Despite his status as a pioneer of black footballers in Argentina, he is not widely known today within his own country or in the rest of the world.