The teams will be drawn into twelve groups of four, and will play each other home-and-away in a round-robin format. The matchdays will be 15 September, 29 September, 20 October, 3 November, 30 November–1 December, and 14–15 December 2011.[2]
The top two teams in each group will advance to the round of 32, where they will be joined by the eight third-placed teams from the Champions League group stage.
For the group stage draw, teams from the same national association could not be drawn against each other. Moreover, the draw was controlled for teams from the same association in order to split the teams evenly for maximum television coverage. For example, if there were two teams from the same association, each team was drawn into a different set of groups (A–F, G–L); if there were four teams from the same association, each team was drawn into a different subset of groups (A–C, D–F, G–I, J–L).
The fixtures were decided after the draw. On the first four matchdays, when matches will be played only on Thursdays, six groups will play their matches at 19:00 CET/CEST, while the other six groups will play their matches at 21:05 CET/CEST, with the two sets of groups (A–F, G–L) alternating between each matchday. On the final two matchdays, when matches will be played on both Wednesdays and Thursdays, the two sets of groups will be divided into four smaller subsets (A–C, D–F, G–I, J–L), with each subset of groups playing on a different day and time. There are other restrictions, e.g., teams from the same city (e.g. Tottenham Hotspur and Fulham) do not play at home on the same matchday (UEFA tries to avoid teams from the same city play at home on the same day), and Canadian teams do not play at home on the last matchday due to cold weather.
If two or more teams were equal on points on completion of the group matches, the following criteria would be applied to determine the rankings:[5]
higher number of points obtained in the group matches played among the teams in question;
superior goal difference from the group matches played among the teams in question;
higher number of goals scored in the group matches played among the teams in question;
higher number of goals scored away from home in the group matches played among the teams in question;
If, after applying criteria 1) to 4) to several teams, two teams still have an equal ranking, the criteria 1) to 4) will be reapplied to determine the ranking of these teams;
superior goal difference from all group matches played;
higher number of goals scored from all group matches played;
higher number of coefficient points accumulated by the club in question, as well as its association, over the previous five seasons.
América
5'
San Carlos
Puerto Rico Islanders
Municipal
Alianza
Camptown
D.C. United
Youth Milan
Camagüey
Montreal Impact
Caledonia AIA
Olimpia
Tempête