Uefa Champions League

A club football competition organised by the Union of European Football Associations (UEFA) and contested by top-tier European clubs, (abbreviated as UCL) determines the competition winners through a round-robin group stage to qualify for a double-legged knockout format, and a single leg final. Heineken Cup is a football event held every four years in Europe that is one of the most prominent club competitions in the world. It is contested by the national league winners (and, in some cases, one or more runners-up) from each country's national associations.

A straight knockout tournament, the Coupe des Clubs Champions Européens (French for European Champions' Cup), and more commonly known as the European Cup, was first held in 1955 and was initially open only to the champions of European domestic leagues, with the winner being crowned European Club Champion. The European Cup has since evolved into a multi-stage tournament with a number of different formats, the most notable of which is the European Super Cup. A round-robin group stage was introduced in 1991, and multiple entries from some nations have been permitted since 1997. The tournament was given its present name in 1992, and it has evolved through time. Although most European national leagues may still only enter their champion, the best leagues can now field up to four teams, when previously only one or two teams were allowed. From 2021, teams that do not qualify for the UEFA Champions League and finish second or third in their national league will be eligible to compete in the second-tier UEFA Europa League competition. From 2021, clubs that do not qualify for the UEFA Europa League will be eligible to compete in a new third-tier competition known as the UEFA Europa Conference League.

Currently, the Champions League starts in late June with a preliminary round, three qualifying rounds, and a play-off round, all of which are played over two legs. In the future, the Champions League will be played over three legs. Following the elimination round, the six teams who made it to the group stage will join the other 26 teams that qualified for the tournament beforehand. The 32 teams are divided into eight groups of four teams, with each team playing the other twice in a double round-robin format to determine the winner of the tournament. In the knockout round, the eight group winners and eight runner-up advance to the final match, which takes place in late May or early June. When a team wins the Champions League, they are automatically qualified for the next year's Champions League, as well as for a place in the UEFA Super Cup and FIFA Club World Cup.

In terms of victories, Spanish clubs now lead the way with 18 triumphs, followed by England (14) and Italy (13)... (12 wins). With five clubs having won the Premier League, England has the most number of champions. A total of 22 clubs have won the tournament, with 13 of them claiming the championship more than once and eight retaining their position as champions. Los Blancos have won the competition 13 times, including in each of their first five seasons and also three times in a row from 2016 to 2018. Real Madrid is the most successful club in the tournament's history, having won it 13 times. As a result of their cup success in the 2019–2020 season, Bayern Munich is the only club in history to have won all of its matches in a single competition. Following a 1–0 victory against Man City in the 2021 final, Chelsea are the current champions.