The 2021 AFC Cup knockout stage was played from 25 August to 5 November 2021.[1] A total of 8 teams competed in the knockout stage to decide the champions of the 2021 AFC Cup.[2] Teams from ASEAN Zone did not compete in the knockout stage, due to the cancellation of group stage matches in ASEAN Zone.[3]
In the knockout stage, the eight teams played a single-elimination tournament. Each tie was played as a single match. Extra time and penalty shoot-out were used to decide the winners if necessary (Regulations Article 9.3 and 10.1).
The schedule of each round is as follows (W: West Asia Zone; C: Central Asia Zone).[1] Matches in the West Asia Zone will be played on Mondays and Tuesdays, while matches in the Central Zone and the Inter-zone play-offs will be played on Tuesdays and Wednesdays.
The bracket of the knockout stage was determined as follows:
Round
Matchups
Zonal semi-finals
(Matchups and order of legs determined by identity of best runners-up: In West Asia Zone, the first team listed host first leg, and the second team listed host second leg. In ASEAN Zone, the first team listed host the match)
West Asia Zone
If best runners-up from Group A
WSF1: Group C winners vs. Group A winners
WSF2: Group A runners-up vs. Group B winners
If best runners-up from Group B
WSF1: Group A winners vs. Group B winners
WSF2: Group B runners-up vs. Group C winners
If best runners-up from Group C
WSF1: Group B winners vs. Group C winners
WSF2: Group C runners-up vs. Group A winners
ASEAN Zone
If best runners-up from Group G
ASF1: Group G winners vs. Group I winners
ASF2: Group H winners vs. Group G runners-up
If best runners-up from Group H
ASF1: Group H winners vs. Group G winners
ASF2: Group I winners vs. Group H runners-up
If best runners-up from Group I
ASF1: Group I winners vs. Group H winners
ASF2: Group G winners vs. Group I runners-up
Zonal finals
(Order of legs decided by draw)
West Asia Zone
WF: Winners of WSF1 vs. Winners of WSF2
Central Asia Zone
CF: Group E winners vs. Group F winners
ASEAN Zone
AF: Winners of ASF1 vs. Winners of ASF2
Inter-zone play-off semi-finals
(Matchups and order of legs decided by draw, involving winners of Group D, Group J, CF, and AF)
IZSF1
IZSF2
Inter-zone play-off finals
(Winners of IZSF1 host first leg, Winners of IZSF2 host second leg)
IZF: Winners of IZSF1 vs. Winners of IZSF2
Final
(Winners of WF host the match, as alternated from previous season's final)
The West Asia Zonal semi-finals were played over one leg, with the home team determined by the draw mechanism based on which group runners-up qualify. A group winner hosted the match against a group runner-up. If two group winners played each other, one of the group winner (whose group runner-up qualify) hosted the match.[2]
The West Asia and Central Asia Zonal final were played over one leg, with the home team decided by draw. The winners of the West Asia Zonal final advanced to the final, while the winners of the Central Asia Zonal final advanced to the Inter-zone play-off semi-finals.
After matches in ASEAN Zone was cancelled, there were only three teams which qualified to the Inter-zone play-off semi-finals, i.e., the winners of the South Asia Zone (Group D), the winners of the East Asia Zone (Group J), and the winners of the Central Zonal final. The three Zonal champions were drawn into two pairings where one club got a bye to the Inter-zone play-off final, which happened for Lee Man. The matchups and order of legs decided by draw, without any seeding with the winner of Central Zonal Final hosting the match and the winner of South Asia Zone being the away team.[4]
In the Inter-zone play-off final, the two teams which advanced from the Inter-zone play-off semi-finals played each other, with the order of legs determined by the Inter-zone play-off semi-final draw. The winners of the Inter-zone play-off final advanced to the final.
The final was played over one leg, between the winners of the West Asia Zonal final and the winners of the Inter-zone play-off final. The home team was determined on a rotation basis, with the match hosted by the winners of the West Asia Zonal final, as in the case of odd-numbered years (Regulations 9.1.2).[2]
Al-Ahed
Al-Salt
Al-Muharraq
Al-Kuwait
ATK Mohun Bagan
Ahal
Nasaf
Lee Man
