Palmeiras booked their spot in the Copa Libertadores knockout rounds, while Nacional claimed their first win of the group stage on Wednesday.
Goals from Keno and Lucas Lima saw Palmeiras record a 2-0 victory over Boca Juniors in Buenos Aires.
Keno opened the scoring five minutes before half-time, heading in a Marcos Rocha cross from the right.
Brazil international Lucas Lima sealed the result with a 35-yard chip after Boca goalkeeper Agustin Rossi was left stranded having come to clear.
Palmeiras are top of Group Eight on 10 points, five clear of Boca.
In Group Six, Nacional recorded a much-needed 4-0 win over Real Garcilaso in Montevideo.
A 25-yard free-kick from Sebastian Rodriguez put the hosts ahead before they struck three times in the final 10 minutes.
Guzman Corujo headed in Nacional's second before Leandro Barcia and Gonzalo Bergessio sealed the victory.
Nacional climbed into second in the group on five points, four behind Santos and one clear of Estudiantes and Real Garcilaso.
In Group One, Monagas stunned Defensor Sporting 1-0, while Atletico Tucuman cruised past The Strongest 3-0 in Group Three.
Flamengo and Santa Fe played out a 0-0 draw in Bogota in Group Four.
