2011 Copa Libertadores knockout stage

If still tied after extra time, the title would be decided by penalty shootout.

If two teams from the same association reach the semifinals, they would be forced to play each other.

In each tie, the higher-seeded team played the second leg at home.

Note: The original kickoff time was 21:50, but the match was delayed due to floodlight failure.

Note: The match was moved from Estadio José Amalfitani as the home stadium of Vélez Sársfield was closed after fans fired volleys of flares during their Clausura match against Banfield.

If the teams were tied on points and goal difference at the end of regulation in the second leg, the away goals rule would not be applied and 30 minutes of extra time would be played.

If still tied after extra time, the title would be decided by penalty shootout.