The 2021 AFC Champions League knockout stage was played from 13 September to 23 November 2021.[1] A total of 16 teams competed in the knockout stage to decide the champions of the 2021 AFC Champions League.[2]
Qualified teams
The group winners and three best runners-up in the group stage from each region advanced to the round of 16, with both West Region (Groups A–E) and East Region (Groups F–J) having eight qualified teams.
If two group winners played each other, the group winner marked with * hosted the match.[3]
West Region
Combination according to the three qualified teams
One-leg matches (13–14 September 2021)
Qualified
1A vs
1B vs
1C vs
1D vs
1E vs
2A/2B/2C
1B*
1A
2A
2B
2C
2A/2B/2D
1D
2D
2A
1A*
2B
2A/2B/2E
1E
2E
2A
2B
1A*
2A/2C/2D
1C*
2D
1A
2A
2C
2A/2C/2E
2C
2E
1E*
2A
1C
2A/2D/2E
2D
2E
2A
1E*
1D
2B/2C/2D
2D
1C*
1B
2B
2C
2B/2C/2E
2C
1E
2E
2B
1B*
2B/2D/2E
2D
1D*
2E
1B
2B
2C/2D/2E
2D
2E
1D*
1C
2C
East Region
Combinations according to the three qualified teams
One-leg matches (14–15 September 2021)
Qualified
1F vs
1G vs
1H vs
1I vs
1J vs
2F/2G/2H
1G*
1F
2F
2G
2H
2F/2G/2I
1I
2I
2F
1F*
2G
2F/2G/2J
1J
2J
2F
2G
1F*
2F/2H/2I
1H*
2I
1F
2F
2H
2F/2H/2J
2H
2J
1J*
2F
1H
2F/2I/2J
2I
2J
2F
1J*
1I
2G/2H/2I
2I
1H*
1G
2G
2H
2G/2H/2J
2H
1J
2J
2G
1G*
2G/2I/2J
2I
1I*
2J
1G
2G
2H/2I/2J
2I
2J
1I*
1H
2H
Format
In the knockout stage, the 16 teams played a single-elimination tournament, with the teams split into the two regions until the final. All ties were played as a single-leg match (Regulations Article 9.1).[4]Extra time and penalty shoot-out were used to decide the winners if necessary (Regulations Article 9.3 and 10.1).[2]
The quarter-finals were played over one leg, with the matchups and home team decided by draw held on 17 September at 15:00 (UTC+8) in Kuala Lumpur, Malaysia.
The final was played over a single leg on 23 November. The host was determined on a rotational basis, with the match hosted by team from the West Region in odd-numbered years (Regulations 9.1.2).[2]
