Lionel Messi came off the bench and twice struck the woodwork against Paraguay as an earlier goal set Argentina on their way to a third consecutive win in South American World Cup qualifying.
A third-minute goal from Nicolas Otamendi was just enough for Lionel Scaloni's team.
Darwin Nunez struck a stoppage time penalty as Uruguay fought back for a 2-2 draw with Colombia in Barranquilla while a stunning 85th-minute equaliser from Eduard Bello earned Venezuela a rare draw in Brazil.
Ecuador got their first points of these 2026 World Cup qualifiers with a last gasp 2-1 win against Bolivia.
Messi's fight for full fitness inevitably dominated the build-up to Argentina's attempt to maintain their 100 per cent record and the seven-time Ballon d'Or winner started on the bench with Julian Alvarez and Lautaro Martinez leading the attack.
But it was veteran defender Otamandi who provided the moment of attacking inspiration, meeting a Rodrigo De Paul corner with a brilliant volley at the back post.
Atletico Madrid midfielder De Paul went close to doubling the lead three minutes before the break when he struck the post and moments later Nicolas Gonzalez fired just wide.
Messi replaced Alvarez in the 53rd minute as Scaloni looked to break down a disciplined and well organised Paraguay side but the woodwork foiled their talisman.
An inswinging corner from the right almost snuck in, but struck the post and then, after winning a free kick on the edge of the box, Messi curled his shot against the same post.
Brazil held by Venezuela
Brazil have never lost to Venezuela in a competitive fixture and have only once before, in 2009, failed to beat the 'Vinotinto' in World Cup qualifying, but they were left frustrated after Bello's brilliant late leveller.
Brazil took the lead when Neymar had a shot pushed wide in the 49th minute and from the resulting corner, taken by the striker, Arsenal defender Gabriel rose at the near post to angle home a fine header.
The goal forced Venezuela into a more adventurous approach and Wilker Angel flashed a header just wide from a 62nd-minute corner.
Rodrygo then found himself in a great position in the box but the Real Madrid winger blasted his shot into the side netting.
With five minutes left, the home crowd in Cuiaba were left stunned when Jefferson Savarino whipped in a cross and Bello lept acrobatically to blast a spectacular overhead kick past Ederson.
The result leaves Brazil in second place in the 10-team qualifying standings, two ahead of Colombia and two behind Argentina.
Nunez spot on for Uruguay
Colombia paid the price for squandering a series of chances to put the game to bed after taking a 2-1 lead in the 52nd minute through Mateus Uribe.
James Rodriguez put Colombia ahead in the 35th minute, bringing down a cross from Santiago Arias with his right foot and then drilling home with his left.
Uruguay drew level just a minute after the restart when Mathias Olivera was left unattended to head home a Nicolas de la Cruz corner.
But Colombia restored their lead when Luis Diaz burst inside from the left flank and fed Rafael Borre, whose low cross was tucked home by Uribe.
Rodriguez saw a low shot from inside the box strike the post and a minute later fed Jhon Arias, who clipped his shot against the bar.
Uruguay escaped with a point after Colombia goalkeeper Camilo Vargas rushed off his line and collided with Maximiliano Araujo.
Vargas was dismissed for a second yellow card and Liverpool striker Nunez kept his cool to bury the penalty and give Marcelo Bielsa's side a precious point.
Paez makes history for Ecuador
Kendry Paez, the 16-year-old Ecuadorean prodigy, became the youngest player to score in a Conmebol World Cup qualifier when he put his team ahead against Bolivia in La Paz with a composed finish in the 45th minute.
A great shot on the turn from Rodrigo Ramallo levelled for Bolivia before a defensive lapse allowed Kevin Rodriguez to grab the winner for Ecuador in the sixth minute of stoppage time to leave Bolivia still without a point.
A second half goal from Diego Valdes and a Marcos Lopez stoppage-time own goal gave Chile a 2-0 win over Peru to leave them in fifth place, level on four points with Uruguay and Venezuela. Peru and Paraguay are currently outside the qualifying spots with a point each.
