The 2009 Copa Libertadores de América (officially the 2009 Copa Santander Libertadores de América for sponsorship reasons) was the 50th edition of the Copa Libertadores de América, CONMEBOL's premier annual international club tournament.
At each stage of the tournament teams receive 3 points for a win, 1 point for a draw, and no points for a loss. If two or more teams are equal on points, the following criteria will be applied to determine the rankings in the group stage:
superior goal difference;
higher number of goals scored;
higher number of away goals scored;
For the first stage, round of 16, quarterfinals, and semifinals, the fourth criteria is replaced by a penalty shootout if necessary. The finals have their own set of criteria; see the finals section for more details.
In the First Stage, twelve teams played a two-legged tie (one game at home and one game away) against another opponent. The winner of each tie advanced to the Second Stage. Team #1 played the second leg at home.
The last four stages of the tournament (round of 16, quarterfinals, semifinals, and finals) form a single-elimination tournament, commonly known as a knockout stage. Sixteen teams advanced into the first of these stages: the third stage.
The 16 qualified teams were seeded according to their results in the Second Stage. The top teams from each group were seeded 1-8, with the team with the most points as seed 1 and the team with the least as seed 8. The second-best teams from each group were seeded 9-16, with the team with the most points as seed 9 and the team with the least as seed 16.
A. ^ Guadalajara and San Luis withdrew from the tournament following concerns raised by both Nacional and São Paulo over the H1N1 flu outbreak in Mexico, South American teams refused to travel to Mexico to play the match; no agreement was reached on alternative venues for the first-leg matches, both scheduled to be played in Mexico. Both Guadalajara and San Luis were later secured a place in the round of 16 for the 2010 Copa Libertadores.