As Medel shielded the ball out of play for a goal kick, Messi gave the defensive midfielder a small shove.
Medel, renowned for his short fuse, reacted furiously and confronted Messi, bumping his shoulder into the Argentine while leaning his head forward.
Messi held his hands up to proclaim his innocence as the shorter Medel proceeded to barge into Messi’s chest four times.
The five-time Ballon d’Or winner did not respond to any of the provocation, leaving his arms raised until other players came to intervene.
However, referee Mario Diaz de Vivar rushed over to the incident and hastily brandishes red cards to both Messi and Medel.
Both players seemed shocked at the decision and while Messi held out his arms in bemusement, Medel sought out the official but was restrained by team-mates.
Seven Argentina players surrounded Diaz de Vivar as his assistant joined his side, trying to calm the situation.
Several little disagreements played out between both teams as management eventually flooded onto the field to try to resolve the vitriol.