Venezuela recorded a shock 1-0 win over Argentina which left Uruguay top after the second round of South American qualifiers for the 2014 World Cup.
Argentina's impressive 4-1 win over Chile on Friday was hastily forgotten as Venezuela took their first points off the two-time World Cup winners in 19 attempts.
Fernando Amorebieta scored the game's only goal from a Juan Arango corner mid-way through the second half.
"In these qualifiers we're going full out, this is an historic night and we must enjoy it," Venezuela captain Arango told Reuters.
Argentina coach Alejandro Sabella was magnanimous in defeat, saying "We were superior for the first 25 minutes but we came up against a well-prepared Venezuela."
Elsewhere, Diego Forlan hit his 32nd international goal as Uruguay were held to a 1-1 draw in Paraguay.
Uruguay went top of the standings with four points after the draw at the Defensores del Chaco.
"This [qualifying] championship is even, no team can consider themselves superior," Uruguay coach Oscar Tabarez said.
Chile bounced back from defeat in Buenos Aires with a hard-fought 4-2 home victory over Peru, while Colombia secured a rare 2-1 away victory over Bolivia in their La Paz stronghold.