Argentinian side Boca Juniors became the only team in the Copa Libertadores with a perfect record as they beat Guarani 3-1 for their fourth win in four games.
The six-time champions eased past one of the tournament's weaker sides with goals by Martin Palermo, Rodrigo Palacio, and Juan Roman Riquelme.
Guarani pulled a goal back through Miguel Paniagua, who took on three defenders and the goalkeeper before scoring.
"This was a good win for us despite the fact we didn't play our best," said Riquelme after the game. "I hope we can improve from now on because I would really like to be able to give our fans yet another Copa Libertadores."
Elsewhere Brazilian side Sao Paulo came back from a goal down to beat Uruguay's Defensor Sporting 2-1 at Morumbi stadium.
A huge mistake by keeper Rogerio Ceni put the visitors ahead in the 38th minute.
Ceni seemed to have Diego Souza's free-kick under control but then incredibly dropped the ball inside his own goal.
But Sao Paulo struck back in the second half when striker Borges scored twice in the 70th and 74th minutes to practically assure the Brazilians of qualification for the last 16.
Diego Souza was then sent off in the final minute of the game.
An Claudio Bieler own goal in the second minute of injury time helped Chilean giants Colo Colo to rescue an 1-1 draw against reigning Copa Libertadores champions Liga Deportiva de Quito in Ecuador.
Jairo Campos had put the hosts ahead after 48 minutes, but in stoppage time Luis Mena's cross bounced off Bieler to give the Chilean's a point.
The Santiago-based team took the lead in Group One with seven points, one more than Brazilian outfit Sport Recife and four more than Palmeiras and Liga.