The team, known as the 'Wild Boars', are honoured guests at the Youth Olympics in the Argentine capital after their rescue gripped the world.
Dressed in violet jerseys with the team logo of the record Argentine champions, they faced River's under-13 team, entering the pitch to loud applause from their opponents.
For the record the final score was 3-3.
"During the rescue operation many people from around the world came to Thailand to collaborate in order to save them, to rescue them; they feel they owe everyone around the world."
The team were greeted by Rodolfo D'Onofrio, president of River Plate, whose vast stadium was the site of the 1978 World Cup final.
"It's really a spectacular moment because these boys have lived really terrible moments," D'Onofrio said. "We are very happy to receive them to play a one-hour football game.
"We offered them the complete equipment... today they were players of River Plate".
They survived nine days on water dripping from rocks before they were discovered on a muddy mound by divers.
A dramatic, international rescue effort ended on July 10 when they were all brought out safely after an ordeal that made headlines around the world.
They have since been showered with invitations, among them to fly to the Argentine capital and attend the Youth Olympic Games.
The boys, who were also guests of honour at the Games opening ceremony in Buenos Aires on Saturday, will leave on Tuesday.