Neymar scored his record 78th and 79th goals for Brazil in a 5-1 World Cup qualifying win over Bolivia, putting him two above the total of three-time World Cup winner Pelé as the Selecao's top goal scorer.
Earlier, Uruguay beat Chile 3-1 in Montevideo in the first official match for coach Marcelo Bielsa for the hosts.
Uruguay did not play either of their two veteran goalscorers - Edinson Cavani or Luis Suárez - as the team goes through a rebuilding process under the Argentinian coach.
All 10 teams in the region will play their second round on Tuesday.
The 2026 edition of the World Cup in the United States, Mexico and Canada is expanding to a 48-team format. The leading six positions in South America will secure a direct spot. The seventh-place team will contest an intercontinental playoff for a berth.
Brazil fans did not know how the team would react under new coach Fernando Diniz, who is in a caretaker position until the next Copa America, possibly to be replaced by Carlo Ancelotti.
Supporters were also wondering how competitive Neymar would be after his transfer out of European soccer and return from injury.
The doubts didn't last long.
Neymar missed a penalty in the 17th minute, which was saved by goalkeeper Billy Viscarra, but he dribbled through the Bolivian defence during the entire match.
He opened space for Raphinha to shoot in the 24th minute. Viscarra saved again, but Rodrygo had the rebound to finish from close range.
Brazil had several other opportunities to double their lead in the first half, but failed. Two minutes after the break the second goal came in a crossed shot by Raphinha, who played because Vinicius Júnior is injured.
In the 53rd minute, Rodrygo scored his second goal after an assist by Bruno Guimarães.
Neymar scored his record-breaking goal in the 61st minute from close range after a low cross that found him near the penalty spot. His second came in added time in similar fashion, also with a low cross from Raphinha that created the clear opportunity for the 31-year-old striker.
Bolivia scored a consolation goal in a counter-attack in the 78th minute through Victor Abrego.
Brazil next play at Peru on Tuesday, the same day Bolivia will host World Cup champions Argentina.
Bielsa's reshaping of Uruguay started with two goals by veteran Nicolás de la Cruz and another by captain Federico Valverde.
Uruguay opened the scoring in the 38th minute with de La Cruz following quick passing into the box that started with Manuel Ugarte, one of the new pivotal players of the team.
Later, Darwin Núñez wasted three more opportunities for Uruguay, giving fans hope there was more to come.
And it did in added time, when Valverde hit the ball hard from the edge of the box and past goalkeeper Brayan Cortés.
Chile tried to change the dynamics of the match after the half-time break, but Uruguay kept the pressure on.
Valverde found De La Cruz once more and the midfielder scored the third for the host in the 71st minute, pushing the ball into an empty net.
Uruguay face Ecuador in the next round while Chile host Colombia.