, located in Vicente Lopez, are called La Banda Más Fiel (The most faithful band) according to scientific research of Argentinian supporters by the University of Torcuato Di Tella. Most of the club's fans live in the Northern Zone of Greater Buenos Aires and CABA itself. Platense Supporter Day has been officially celebrated since 2005 every October 8. Club nicknames are Tense and Marrón (The Browns) due to the predominant color of his shirt. Although the most used nickname is El Calamar (The Squid) — since a journalist in the amateur era of Argentine soccer called them that because the club showed great games on stormy days and heavy rains. He said that the players played like squids in their ink and that's where the nickname came from.

Argentinos Juniors is a sports club based in La Paternal, Buenos Aires. The club is most known for its football team, which plays in the Argentinean Primera División. One of the club's nicknames is "Bicho Colorado" (Red Bug), which came from a famous newspaper headline in the 1950s that read "Arrasan los bichos colorados" (Red bugs sweep all before them). The club is also nicknamed El Semillero, meaning the Nursery or The Seed Garden, because of its ability to keep producing world-class football players.

The absolute icon of the club is Diego Maradona, whose career started at Argentinos Juniors. In his honor, the club's stadium is named Estadio Diego Armando Maradona. It holds El Templo del Fútbol museum as well as the murals gallery on the stadium facade, mostly dedicated to Diego. Other famous players who started their careers at Argentinos Juniors are Juan Román Riquelme, Esteban Cambiasso, Juan Pablo Sorín, and Fernando Redondo.

The club is one of the eight Argentinean teams that have won the Copa Libertadores. The continental trophy was won in the club's first entry to the contest, in 1985. The club has had many rivalries, but their first-ever clásico was with Sportivo Italiano, who currently do not play professional football, which has led to their more recent rivalry against Platense with the most prominent clashes in the 80s.

Argentinos Jrs : Platense