Santos came from behind on Wednesday against Mexico's America to win the second leg of their quarterfinal series, 2-1, and win by the same score on aggregate.
Argentine midfielder Daniel Bilos gave America the lead late in the first half, but Santos responded with goals by Jonas and Rodrigo Souto. American returns to action Friday when it plays the first of the two-leg final for the Mexico's Torneo Clausura championship.
Goals by Tcheco and Teco gave Gremio a 2-0 win over Uruguay's Defensor Sporting to even their series, 2-2, and the Brazilian club went through on penalties, 4-2.
Cucuta, playing in the tournament for the first time in its 47-year history, twice came from behind to earn a 2-2 tie at Uruguayan club Nacional on Tuesday and win, 4-2, on aggregate. Ruben Dario Bustos and Leonard Pajoy scored after Gonzalo Castro and Diego Vera had put Nacional ahead.
Paraguayan champion Libertad hosts five-time champion Boca Juniors in the second leg of the other quarterfinal series in Asuncion on Thursday.