Mexican side Toluca has stunned Boca Juniors with a 2-1 away win to go top of Group One in the Copa Libertadores.
Boca took the lead in the 22nd minute when Santiago Silva calmly converted a penalty and the hosts looked set to get their Copa campaign off to the perfect start when goalkeeper Agustin Orion saved Carlos Rodriguez's spot kick in the 51st minute.
But it didn't take long for Toluca to bounce back from the penalty miss when Carlos Esquivel latched onto the end of a long ball and netted the equaliser.
Toluca's comeback was complete when Sinha put Edgar Benitez through as the striker shot over Orion's body to score the winner.
Boca striker Lucas Viatri could have equalised in the last minute, but his long range shot hit the post and resigned the Argentine side to the bottom of the table after the first round of matches.
Toluca midfielder Sinha told Fox Sports believes the win gives his side great confidence of challenging for the Copa Libertadores crown this year.
"Playing here at La Bombonera is very tough as Boca have huge tradition in this tournament," he said. "With dedication and effort you can build big teams. We know that winning away in the Copa Libertadores is very good."
Boca midfielder Cristian Erbes was critical of his side's failed opportunity to take a stranglehold on the group, insisting they must turn around their fortunes immediately.
"We are angry because we wanted to win our first home game in the championship," he said. "We must think about the mistakes we made and correct them."
A duel between Brazilian compatriots saw Atletico Mineiro beat Sao Paulo 2-1 in Group Three.
Two assists by veteran playmaker Ronaldinho helped Atletico Mineiro celebrate the win after a 13-year absence from the Copa Libertadores.
Jo opened the scoring in the 13th minute, while Ronaldinho dribbled past two Sao Paulo defenders before setting up Rever to double the gap in the 27th. Aloisio reduced the gap with seven minutes to go.
Another Brazilian team to win was Fluminense as they saw off Caracas 1-0 in Venezuela, Fred scoring the winner in the 31st minute.
In Chile, Uruguayan giants Penarol claimed an important 2-1 win at Iquique in Group Four.
Fabian Estoyanoff and Juan-Manuel Olivera, one in each half, scored for the winners, while Manuel Villalobos netted the temporary leveller.
Elsewhere in Peru, hosts Real Garcilaso and Colombian champions Santa Fe drew 1-1. Cristian Martinez put the visitors ahead in the 15th minute, but Rolando Bogado levelled with a header in the 75th minute in Group Six.