Tournament Structure
The Copa Libertadores begins with qualification rounds where teams from smaller confederations compete for spots. The tournament then moves to a group stage where 32 teams are divided into eight groups of four teams each. Teams play each other once in their group, and the top two teams from each group advance to the knockout rounds.
Knockout Rounds and Final
After the group stage, the 16 remaining teams enter a knockout phase consisting of round-of-16, quarterfinals, and semifinals. Each knockout match is played as a two-leg tie, with teams playing one match at each team's home stadium. The final is also a two-leg series, and the team with the better aggregate score wins the championship. If scores are tied after both legs, away goals and extra time determine the winner.
Eligibility and Teams
Teams that qualify for Copa Libertadores are the top clubs from South American national leagues. The number of spots each country receives depends on their confederation's ranking and historical performance. Traditional powerhouses like Brazil and Argentina send multiple teams, while smaller nations send fewer representatives.
Scheduling and Format Rules
Matches are typically played midweek or on weekends throughout the tournament season. Teams earn three points for a win and one point for a draw in group play. In knockout matches, there are no draws in regulation, and teams advance based on aggregate score or penalty kicks if needed.
Special Rules
Teams are allowed to make five substitutions per match. The tournament has evolved over time, with recent changes made to accommodate scheduling and create more competitive balance. Some years include additional playoff rounds or adjusted group configurations based on the number of participating teams. 
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