The UEFA Champions League is an annual club association football competition organised by the Union of European Football Associations (UEFA) and contested by top-division European clubs, deciding the competition winners through a round robin group stage to qualify for a double-legged knockout format, and a single leg final. It is the most-watched club competition in the world and the third most-watched football competition overall, behind only the UEFA European Championship and the FIFA World Cup. It is one of the most prestigious football tournaments in the world and the most prestigious club competition in European football, played by the national league champions of their national associations.
Johan Cruyff (pictured in 1972) won the European Cup three times in a row with Ajax.
The two teams line up for the UEFA Champions League Anthem before each match and a flag of the Champions League "starball" logo is waved in the centre circle.
The "starball" logo is incorporated into the design of the competition's official match ball, the Adidas Finale.
AC Milan and Real Madrid are two of the competition's most successful teams.
Association football, commonly known as football, or soccer, is a team sport played between two teams of 11 players each, who primarily use their feet to propel a ball around a rectangular field called a pitch. The objective of the game is to score more goals than the opposing team by moving the ball beyond the goal line into a rectangular-framed goal defended by the opposing team. Traditionally, the game has been played over two 45-minute halves, for a total match time of 90 minutes. With an estimated 250 million players active in over 200 countries and territories, it is the world's most popular sport.
The attacking player (No. 10) attempts to kick the ball into the net behind the opposing team's goalkeeper (here wearing red and yellow) to score a goal.
An early draft of the original hand-written 'Laws of the Game' drawn up on behalf of The Football Association by Ebenezer Cobb Morley in 1863 on display at the National Football Museum, Manchester, England
The Aston Villa team in 1897, after winning both the FA Cup and the English Football League
The Zamalek team in 1921, after winning the Sultan Hussein Cup, the first title in Egyptian football history, 1921