Bolivia beat a short-handed Argentina team 2-0 in a CONMEBOL World Cup qualifier at the Estadio Hernando Siles in La Paz on Tuesday.
Argentina were playing without Lionel Messi, after the Barcelona forward was given a four-match ban from FIFA for insulting the assistant referee in the national team's 1-0 win against Chile on Thursday.
Edgardo Bauza's team have struggled mightily when playing without Messi, winning just once in eight times including the latest result against Bolivia.
The visitors nearly had an opener against the run of play in the 29th minute, but Carlos Lampe saved Angel Di Maria's shot from the centre of the penalty area after he had been played through by Angel Correa.
Two minutes later, Bolivia took the lead when Juan Carlos Arce headed home past Sergio Romero from a Pablo Escobar pass to put the hosts ahead 1-0 at half-time.
Marcelo Moreno doubled Bolivia's advantage soon after the break, firing home an Enrique Flores cross with a powerful right-footed shot in the 52nd minute.
Argentina continued to struggle without their talisman and could not find a way back into the game, meaning it's more missed points for Bauza's team, who will now slip in the qualifying table after rising to third following the win against Chile.
"We are alive. This is a fight that we will keep fighting," Bauza told a postmatch news conference, before admitting there were big concerns within the squad. "Yes, the players are worried because no one likes to lose."
Argentina's next games will be in August away to Uruguay and in Buenos Aires against Venezuela. In October, the 2014 World Cup finalists face Peru at home and Ecuador away.
Brazil booked their spot at next year's World Cup in Russia with a dominant 3-0 win over Paraguay.
Tite's men are 11 points ahead of fifth-placed Argentina and 10 in front of Uruguay in fourth, and therefore cannot be caught as both nations are still to play each other.
Liverpool's Philippe Coutinho curled in a low opener and Neymar capped an eventful evening with a goal in the second half before Marcelo added a late third.
Barcelona forward Neymar, captaining the side, missed a penalty and saw an effort chalked off for offside on an evening when he was routinely on the end of rough treatment from the Paraguay defenders.
In Quito, James Rodriguez and Colombia built on the momentum from Thursday's win against Bolivia with a 2-0 defeat of Ecuador.
James fired the visitors into an early lead in the 20th minute, poking home from close range to put his team 1-0 up.
And 15 minutes later, Juan Cuadrado added a second for Jose Pekerman's team, with James setting up the Juventus man to make it 2-0 ahead of half-time.
Ecuador failed to break down a resolute Colombia defence in the second half, with the result pushing the visitors past Argentina into at least third
Alexis Sanchez and Chile also took advantage of Argentina's loss, hammering Venezuela 3-1 at home to take all three points and move past rivals Argentina in the table.
The hosts were on the board in the fifth minute, with Sanchez beating Wuilker Farinez from a free kick to equal Marcelo Salas as Chile's all-time leading international scorer with 37 goals.
Two minutes later Esteban Paredes fired home a Charles Aranguiz pass from the centre of the penalty area to double his team's lead. Paredes would score his second 15 minutes later to effectively end proceedings just past the 20-minute mark.
Salomon Rondon pulled one back for Venezuela in the 63rd minute, but the game was out of reach for the visitors who are bottom of the qualifying table with no shot at a chance at Russia 2018.
Tuesday's other match saw Peru upset Uruguay 2-1 at the Estadio Nacional de Lima.
Carlos Sanchez put the visitors in front on the half hour, but goals from Paolo Guerrero and Edison Flores pulled the tie back in Peru's favour.
Uruguay's hopes of salvaging anything from the match were dashed when Pachuca winger Jonathan Urretaviscaya was sent off for a second bookable offence in the 76th minute.