Argentina took their unbeaten run to 25 matches and moved a step closer to qualifying for the World Cup with a hard-fought 1-0 win over Peru on Thursday.
Lautaro Martinez scored the only goal of the game two minutes before the break with a powerful header while Yoshimar Yotun missed a second half penalty for Peru.
On his first start for his country, Raphinha scored a brace as Brazil all but mathematically booked their place at the World Cup with a 4-1 thrashing of Uruguay.
Neymar and Gabriel Barbosa scored the other goals while Luis Suarez notched Uruguay's consolation.
Brazil top the single South American qualifying group by six points from Argentina, who have a nine point gap to those that could deny them a berth at Qatar 2022.
Argentina last lost in the 2019 Copa America semi-finals -- 2-0 against Brazil.
Since then the South American giants have been unstoppable, beating Brazil twice on their run, including earlier this year in the 2021 Copa America final.
- Rash challenges -
In the early stages in windy Buenos Aires, Peru looked capable of causing an upset, but striker Gianluca Lapadula prodded their bets chance straight into Argentina goalkeeper Emiliano Martinez's midriff.
Argentina center-back Cristian Romero thought he had put the hosts in front when headed in a Rodrigo De Paul free-kick, only to be flagged offside.
Peru's approach was industrious and crude, with Lionel Messi subjected to several rash challenges.
Argentina took the lead two minutes before half-time as Lautaro Martinez sent a bullet header from Nahuel Molina's cross straight over goalkeeper Pedro Gallese's head.
Peru were given a lifeline 20 minutes into the second half after bringing on the pacey Jefferson Farfan, who almost immediately broke clear of the Argentina defense before Emiliano Martinez brought him down in the box.
But Yotun's wild penalty clipped the top of the bar to give Martinez a huge let-off.
Argentina had the ball in the net for a third time two minutes from the end but Guido Rodriguez's header was ruled out for a push on Marcos Lopez.
"You could see we were tired today," admitted Argentina coach Lionel Scaloni, after an "exhausting" three matches in the space of a week.
"We got on with it and took the points, which is what we wanted."
- Muslera limits damage -
Brazil got off to a blistering start in sweltering Manaus when defensive midfielder Fred -- displaying a vision and touch rarely seen by his club Manchester United's fans -- chipped a ball over the defense for Neymar to latch onto, round goalkeeper Fernando Muslera and then fire home between the legs of a defender on the line.
The dominant hosts stretched their lead inside the first quarter as Lucas Paqueta crossed from the left to Neymar, whose deflected shot fell kindly for Raphinha at the back post to slot home.
Muslera was at times a one-man barrier preventing a humiliating scoreline as Brazil finished with 13 shots on target.
His most telling contribution was a double save in a matter of seconds to prevent either Gabriel Jesus or Raphinha from extending Brazil's lead, but a diving one-handed stop to repel a Barbosa shot was his most spectacular intervention.
Brazil put the game to bed just before the hour mark on a rapier counter-attack with Neymar teeing up Raphinha to thrash home a shot off the far post.
Uruguay, who earlier had an Edinson Cavani strike ruled out for offside, scored a consolation 13 minutes from time through Suarez's brilliant low free-kick.
Muslera slightly tarnished his earlier brilliance by letting Barbosa's header through his fingers for Brazil's fourth.
- VAR chaos in Colombia -
Colombia and Ecuador played out a fractious ill-tempered 0-0 draw in Barranquilla that did little to boost either side's qualification hopes as they battle for a top four finish.
It lasted more than 15 minutes over the regulation 90 due to two interminable second half VAR breaks.
The first overturned a decision to award Ecuador a penalty while the second, 10 minutes into time added on, eventually chalked off what had appeared to be a winning goal by giant Colombia center-back Yerry Mina.
The petulant encounter ended with Colombian players surrounding Peruvian referee Diego Haro to harangue him over the disallowed strike.
Bolivia recorded a second straight victory in La Paz to revitalize their qualification hopes as goals by Rodrigo Ramallo, Moises Villarroel, Victor Abrego and Roberto Fernandez saw them cruise to a 4-0 win over Paraguay, who sacked coach Eduardo Berizzo a couple of hours later.
A brace from Edgar Pulgar and one from English-born Ben Brereton gave Chile a 3-0 win over rock-bottom Venezuela.