The 2018 Copa Sudamericana final stages were played from 21 August to 12 December 2018.[1] A total of 16 teams competed in the final stages to decide the champions of the 2018 Copa Sudamericana.[2]
Starting from the round of 16, the teams were seeded according to the second stage draw, with each team assigned a "seed" 1–16 corresponding to the tie they win (O1–O16) (Regulations Article 22.c).[2]
Each tie was played on a home-and-away two-legged basis, with the higher-seeded team hosting the second leg (Regulations Article 22.d).
In the round of 16, quarterfinals, and semifinals, if tied on aggregate, the away goals rule would be used. If still tied, extra time would not be played, and the penalty shoot-out would be used to determine the winner (Regulations Article 27).
In the finals, if tied on aggregate, the away goals rule would not be used, and 30 minutes of extra time would be played. If still tied after extra time, the penalty shoot-out would be used to determine the winner (Regulations Article 28).
The first legs were played on 21–22 August, 18–20 and 26 September, and the second legs were played on 19, 25, 27 September, and 2–4 October 2018.[3][4]
In the finals, if tied on aggregate, the away goals rule would not be used, and 30 minutes of extra time would be played. If still tied after extra time, the penalty shoot-out would be used to determine the winner (Regulations Article 28).[2]
The first leg was played on 5 December, and the second leg was played on 12 December 2018.