The draw for the group stage took place on August 16th at the InterContinentalKuala Lumpur, Malaysia.[2] The 32 teams were drawn into eight groups of four: four groups each in the West Region (Groups A–D) and the East Region (Groups E–H).[3] For each region, teams were seeded into four pots and drawn into the relevant positions within each group, based on their association ranking and their seeding within their association. Teams from the same association could not be drawn into the same group.
In the group stage, each group will be played in a double round-robin format on home and away basis. The winners and runners-up of each group advance to the round of 16 of the knockout stage.
The teams were ranked according to points (3 points for a win, 1 point for a draw, 0 points for a loss). If tied on points, tiebreakers were applied in the following order (Regulations Article 8.3):[4]
Goals scored in head-to-head matches among tied teams;
If more than two teams were tied, and after applying all head-to-head criteria above, a subset of teams were still tied, all head-to-head criteria above were reapplied exclusively to this subset of teams;
Goal difference in all group matches;
Goals scored in all group matches;
Penalty shoot-out if only two teams playing each other in the last round of the group are tied;
Disciplinary points (yellow card = 1 point, red card as a result of two yellow cards = 3 points, direct red card = 3 points, yellow card followed by direct red card = 4 points);
SepahanACLE
Al-Hussein Irbid
Shabab Al AhliACLE
Istiklol
Al Taawoun
Nasaf
Mohun Bagan SG
Altyn AsyrPS
Al-Wakrah
Al-Quwa Al-Jawiya
Al-Khaldiya
Al-KuwaitPS
Bangkok UnitedACLE
Lee Man
Sanfrecce Hiroshima
Sydney FC
Kaya–Iloilo
Jeonbuk Hyundai Motors
Selangor
Lion City Sailors
Zhejiang
Thep Xanh Nam Định
Persib