The tournament was inaugurated in 1955, at the suggestion of the French sports journalist and editor of L'Équipe Gabriel Hanot,[1] as a continental competition for winners of the European national football leagues, as the European Champion Clubs' Cup, abbreviated to European Cup.
The competition began in 1955/56 using a two-leg knockout format where the teams would play two matches, one at home and one away, and the team with the highest overall score qualifying for the next round of the competition. Entry was restricted to the teams that won their national league championships, plus the current European Cup holder. This qualification system continued until 1992. In the 1992–93 season, the tournament was renamed to UEFA Champions League and in 1997/98, eligibility was expanded to include not just domestic champions but also the best performing runners up according to UEFA's coefficient ranking list[2]. In UEFA's coefficient system, a team finishing second in the Spanish La Liga would be more deserving of an automatic place in the Champions League than a team finishing first in, for example, Polish Orange Ekstraklasa. As a result, the system was restructured to force "weaker" national champions to qualify for the group stages, while other, "stronger" national runners-up would automatically get places.
The Champions League flag is shown on the centre of the pitch before every game in the competition
The UEFA Champions league is open to the league champions of all UEFA member associations (except Liechtenstein, which has no league competition), as well as to the clubs finishing from second to fourth position in the strongest leagues. Since January 2007 the two lowest-ranked league competitions (currently the Andorra and San Marino leagues) can also represent their domestic champions in the Champions League.
The number of places in the competition depends on the association's rank in the UEFA coefficients table:
associations ranked 1 to 3 have four positions,
associations ranked 4 to 6 have three positions,
associations ranked 7 to 15 have two positions,
associations ranked 16 or lower have one position.
In addition to sporting criteria, any club must be licensed by its national association to participate in the Champions league. To obtain a license, club must meet certain stadium, infrastructure and finance requirements.
The tournament consists of several stages and begins with three preliminary knockout qualifying rounds. Different teams start in different rounds, according to their position in domestic league and the UEFA coefficients of their league, while the sixteen top ranked teams spread across the biggest domestic leagues qualify directly.
In the subsequent preliminary round, participating teams are paired, with aggregate winners proceeding into the next round. Qualifying rounds span from mid-July to late August. The losers of the third qualifying round are transferred to the UEFA Cup, while the sixteen winners of the final qualifying round are joined by the sixteen teams who have qualified directly, to participate in the group stage.
Teams are drawn into eight groups of four teams, each team playing every other team in the group twice (home and away). The group stage is played between mid-September and early December. The teams finishing third in their groups are transferred to the UEFA Cup, while the top two teams from every group qualify for the next round. Here the sixteen remaining teams take part in the knock-out stage, which starts in late February and ends with the final match in May.
All qualifying rounds and knock-out ties are two-legged, with each team hosting one match. The team which scores the greater aggregate number of goals qualifies for the next round. The away goals rule applies. Extra time and penalty kicks are used to determine the winner, if necessary. An exception is the final, which is a single match played at a predetermined venue.
The draws are currently structured to ensure that clubs representing the same national association cannot play each other until the quarter-finals. This rule however was lifted for Liverpool's entry in 2006, as England had 5 representatives in the competition. As a result Liverpool were drawn against Chelsea in the group stages. In addition, seeding of the teams according to their UEFA coefficients is used. The competition system has been undergoing changes since the 1991-92 season (see history). The current system was adopted in 2003.
At meeting in Lucerne, 30th of November 2007, UEFA decided to introduce new qualification system[3] for period 2009-2012 which will give automatic qualifying berth to the group stage for 22 teams instead of 16 (6 new entrants: 3rd-placed teams from associations 1-3 + champions from associations 10-12). Remaining 10 teams will be given through a double qualification path: one reserved for the champions of the associations ranked 13 or lower, and one reserved for non-champions of associations ranked 1-15. Both paths will be held independently to each other and each will be given by 5 winners - last participants in group stage. The main idea was to enable champions coming from low-ranked associations much easier access to the main tournament through their head-to-head matches than through matches against non-champions from high-ranked associations which failed to qualify directly for group stage through their domestic league.