[2] The draw for the qualifying stages was held on 20 December 2017, 20:00 PYST (UTC−3), at the CONMEBOL Convention Centre in Luque, Paraguay.
[7] As the identity of the winners of the second stage was not known at the time of the draw, they could be drawn into the same tie with another team from the same association.
If still tied, extra time was not played, and a penalty shoot-out was used to determine the winner (Regulations Article 29).
Tied 1–1 on aggregate, Deportivo Táchira won on away goals and advanced to the second stage (Match C1).
Tied 3–3 on aggregate, Oriente Petrolero won on away goals and advanced to the second stage (Match C3).
Vasco da Gama won 6–0 on aggregate and advanced to the third stage (Match G3).