Boca, Corinthians and Vasco progress
Corinthians were the night's most convincing winners with a comprehensive 3-0 victory over Ecuadorean side Emelec. The first leg ended goalless but it took the Sao Paulo giants just seven minutes to break the deadlock at home through Fabio Santos.
Corinthians missed a hatful of chances but eventually grabbed a second in the 64th minute thanks to Paulinho, before Alex gave them a deserved third five minutes from time.
They will meet another Brazilian side in the quarter-finals after Vasco da Gama knocked out Lanus on penalties.
The Argentine side won 2-1 on the night, to make the aggregate all square at 3-3. Vasco scored all five of their penalties in the shootout and went through 5-4 after Silvio Romero missed Lanus's second spot-kick.
There was some consolation for Argentina, however, thanks to a sterling performance from Boca Juniors. Spurred on by the mercurial Juan Roman Riquelme, the six-time champion beat Union Espanola 3-2 to take the tie 5-3 on aggregate.
Riquelme capped a great performance with a wonderful solo goal in the 67th minute.
Boca will play the winners of the all-Brazilian tie between Fluminense and Inter.