MLS performance in the CONCACAF Champions League
Major League Soccer teams have participated in the CONCACAF Champions League each season since the tournament began its current format in 2008–09. Previously, MLS teams played in the CONCACAF Champions Cup. MLS may send up to five teams to the CONCACAF Champions League each season — up to four from the United States, and up to one from Canada. The first MLS team to finish first in its group was Real Salt Lake in 2010. The best performance by an MLS team to date occurred in 2018, when Toronto FC reached the final, before  losing to Mexico's Guadalajara 4–2 on penalties following a 3–3 scoreline on aggregate. Real Salt Lake, CF Montréal and Los Angeles FC all also reached the final, losing to Monterrey in 2011, América in 2015 and UANL in 2020, respectively. MLS teams have never won the Champions League under its current format since 2008–09, and therefore have not sent a team to the FIFA Club World Cup. Performance by round. The following table shows the number of MLS participants in the Champions League each season, as well as the number of MLS teams that have reached various stages in  the knockout rounds. MLS teams performed poorly during the first two years, as fixture congestion from the Superliga tournament as well as CONCACAF Champions League preliminary rounds meant that MLS teams often fielded teams without their first choice players. Beginning in 2018, the Champions League format was changed to eliminate group play and the knockout round starts with sixteen teams rather than eight. Notes: Performance by opposition in knockout series. The following table shows the performance of MLS teams in the knockout rounds for each home-and-away series for opponents from various leagues. During the first nine seasons of  the Champions League, MLS teams did not play any foreign teams in knockout stage other than Mexico, Costa Rica, and Panama. With the change in tournament format in the 2018 season, specifically with the knockout rounds now including a round of 16, MLS teams play knockout matches against a greater variety of countries. In the Champions League knockout rounds, MLS teams have played Mexican teams more than any other country, in some years facing multiple matchups. Seattle's 2013 quarter-final win over Mexico's UANL was the first time since the Champions League format began in 2008–09 that an  MLS team eliminated a Mexican team in the knockout rounds. Montreal repeated the feat in 2015 when they beat Mexico's Pachuca in the quarter-finals. In 2018, Toronto FC and the New York Red Bulls both advanced to the semi-finals by beating Mexican teams, the first time that two MLS teams eliminated two Mexican teams in the same tournament. In 2020, Los Angeles FC became the first MLS team to eliminate three Mexican teams in the same tournament — beating Mexican opponents in the Round of 16, quarterfinals, and semifinals, before losing in the final to a Mexican team . MLS' improved performance against Mexican teams was attributed to MLS club academies focused on player development, and an increase in player salaries through the league's Targeted Allocation Money (TAM) program. CONCACAF Club Index. The CONCACAF Club Index was introduced in 2018 as a way of seeding the 16 teams in the knockout rounds. The index does not rank clubs but ranks member association qualification slots and is based on the past five prior years' results. Points are awarded as follows: 4 for participation, 3 for a win, 2 for Champions, 1 for draw, and 1 for stage advanced. The  following table shows the index for the five Canadian and American teams. For context, the table also shows the index for the lowest-ranked Mexican slot and the highest-ranked Central American slot. Performance by team. As of 2021, 21 MLS teams have appeared in the CONCACAF Champions League since the inaugural 2008–09 season. Real Salt Lake in 2011, Montreal Impact in 2015, Toronto FC in 2018 and Los Angeles FC in 2020 are the only teams that have played in the competition's final, but all four have failed to win the continental title. Canadian teams in MLS – CF  Montréal, Toronto FC and Vancouver Whitecaps FC – qualify to the Champions League via a separate competition, the Canadian Championship, and they represent the Canadian Soccer Association. The only times MLS standings were used for Canadian teams qualification were the 2014 season to determine the 2015–16 Champions League representative, as the Canadian Championship format was changed that season, and the 2020 season to determine the 2021 Champions League representative, as the 2020 Canadian Championship was postponed indefinitely due to the COVID-19 pandemic. Starting in 2018, the group stage was removed, so MLS teams now start in the Round of 16 (first  round). ǂ – team represents Canada Apps – CCL appearances Pld – games played W, D, L – wins, draws, losses GF, GA, GD – goals for, goals against, goal difference Records. Biggest win: 6 goal margin Portland Timbers 6–0 Alpha United (2014–15 Group stage) Biggest defeat: 5 goal margin Other continental competitions. MLS teams have participated in other continental competitions.