Despite lockdown measures, pictures show supporters, many without a mask, hugging and dancing in the streets after substitute Breno Lopes scored a dramatic stoppage-time header to secure a 1-0 win over Santos.
Fireworks were set off as the team returned home in the early hours of Sunday.
There had been an increased police presence around the Maracana with authorities worried fans would gather outside for what has always been a passionate fixture.
The game itself only sprung into life during the closing stages with Santos seeing its manager, Cuca, sent off moments before Lopes’ 99th-minute header sealed a famous victory for Palmeiras.
The goal sparked delirious scenes with players running over to celebrate with those supporters allowed into the stadium.
Palmeiras had not won the Copa Libertadores since 1999 and now qualifies for the Club World Cup in Qatar later this month, where it could face European champion Bayern Munich.
On social media, the club dedicated its victory “to all families who have lost a loved one and those who are still in the battle against Covid-19.