Argentinian side Velez Sarsfield and Deportivo Quito of Ecuador made it into the round-of-16 from Group Seven of the Copa Libertadores.
Velez Sarsfield ended on top of the group despite a 3-1 home defeat to Uruguay's Defensor Sporting.
Nicolas Olivera put Defensor ahead early in the seventh minute, while Diego Rodriguez widened the gap 30 minutes later and Matias Britos made it 3-0 two minutes after the half-time.
Federico Insua reduced the deficit with a 63rd-minute penalty but Velez failed to maintain the best record in the group stage - which would have allowed them the advantage of playing the second leg of all the remaining games at home.
Velez boss Ricardo Gareca was angry with his side's result in Buenos Aires, telling reporters: "If you play this way, you become eliminated.
"We must fix some aspects in the next stage. All defeats are useful to make decisions. It can not happen again."
Defensor Sporting crashed out though as Deportivo Quito hammered Mexican giants Guadalajara 5-0 with Matias Alustiza netting four goals. The Argentinian forward netted at the 17th, 27th, 70th and 84th, while Fidel Martinez added the other 20 minutes after the break.
Guadalajara defender Jorge Enriquez was sent-off at the 57th minute.
Bolivar saw-off Chile's Universidad Catolica 3-0 to reach the round-of-16.
Pablo Frontini's second-minute goal immediately settled the nerves of the Bolivian side in a must-win game.
Walter Flores long-range strike doubled the lead in the 27th minute before Damian Lizio consolidated the win four minutes after the half-time.
"We knew it was a must-win game for us. Failure was impossible," Lizio told Fox Sports. "We managed the game well after the goals. We could have scored even one more goal."
The other Chilean team in the group, Union Espanola, ended on top even though they lost 2-1 at Junior in Colombia.
Union Espanola scored the first goal of the game, as Emiliano Vecchio netted a tremendous free-kick in the 12th minute.
However, first-half penalties from Sherman Cardenas and Luis Paez gave Junior the win despite the 29th-minute dismissal of keeper Carlos Rodriguez.
Union Espanola failed to equalise despite their man advantage after the break.