The 2019 AFC Champions League knockout stage was played from 18 June to 24 November 2019.[1] A total of 16 teams competed in the knockout stage to decide the champions of the 2019 AFC Champions League.[2]
The winners and runners-up of each of the eight groups in the group stage advanced to the round of 16, with both West Region (Groups A–D) and East Region (Groups E–H) having eight qualified teams.
| width=90 | Region | Group | width=200 | Winners | width=200 | Runners-up |
|---|---|---|---|---|---|---|
| West Region | A |  Zob Ahan | Al-Nassr | |||
| B | Al-Wahda | Al-Ittihad | ||||
| C | Al-Hilal |  Al-Duhail | ||||
| D | Al-Sadd | Al-Ahli | ||||
| East Region | E |  Shandong Luneng |  Kashima Antlers | |||
| F | Sanfrecce Hiroshima | Guangzhou Evergrande | ||||
| G |  Jeonbuk Hyundai Motors | Urawa Red Diamonds | ||||
| H | Ulsan Hyundai | Shanghai SIPG |
In the knockout stage, the 16 teams played a single-elimination tournament, with the teams split into the two regions until the final. Each tie is played on a home-and-away two-legged basis. The away goals rule, extra time (away goals do not apply in extra time) and penalty shoot-out were used to decide the winner if necessary (Regulations Article 11.3).[2]
The schedule of each round was as follows.[1] Up to the semi-finals, matches in the West Region were played on Mondays and Tuesdays, while matches in the East Region were played on Tuesdays and Wednesdays.
| Round | First leg | Second leg | |
|---|---|---|---|
| Round of 16 | 18–19 June 2019 (E), 5–6 August 2019 (W) | 25–26 June 2019 (E), 12–13 August 2019 (W) | |
| Quarter-finals | 26–28 August 2019 | 16–18 September 2019 | |
| Semi-finals | 1–2 October 2019 | 22–23 October 2019 | |
| Final | 9 November 2019 | 24 November 2019 |
The bracket of the knockout stage was determined as follows:
| Round | Matchups | |
|---|---|---|
| Round of 16 | (Group winners host second leg)
| |
| Quarter-finals | (Matchups and order of legs decided by draw, involving four round of 16 winners each in West Region and East Region)
| |
| Semi-finals | (Winners of QF1 and QF3 host first leg, winners of QF2 and QF4 host second leg)
| |
| Final | (Winners of SF1 host first leg, winners of SF2 host second leg, as reversed from previous season's final)
|
In the round of 16, the winners of one group played the runners-up of another group from the same region, with the group winners hosting the second leg, and the matchups determined by the group stage draw.
|+West Region|+East Region
Al-Nassr won 4–3 on aggregate.----Al-Ittihad won 6–4 on aggregate.----Al-Sadd won 4–2 on aggregate.----Al-Hilal won 4–3 on aggregate.
3–3 on aggregate. Kashima Antlers won on away goals.----4–4 on aggregate. Guangzhou Evergrande won 6–5 on penalties.----Urawa Red Diamonds won 4–2 on aggregate.----2–2 on aggregate. Shanghai SIPG won 5–3 on penalties.
The draw for the quarter-finals was held on 2 July 2019.[4] In the quarter-finals, the four round of 16 winners from the West Region (whose identity was not known at the time of the draw) played in two ties, and the four round of 16 winners from the East Region played in two ties, with the matchups and order of legs decided by draw, without any seeding or country protection.
|+West Region|+East Region
Al-Sadd won 4–3 on aggregate.----Al-Hilal won 3–1 on aggregate.
3–3 on aggregate. Urawa Red Diamonds won on away goals.----1–1 on aggregate. Guangzhou Evergrande won on away goals.
In the semi-finals, the two quarter-final winners from the West Region played each other, and the two quarter-final winners from the East Region played each other, with the order of legs determined by the quarter-final draw.
|+West Region|+East Region
Al-Hilal won 6–5 on aggregate.
Urawa Red Diamonds won 3–0 on aggregate.
See main article: article and 2019 AFC Champions League final. In the final, the two semi-final winners played each other, with the order of legs (first leg hosted by team from the West Region, second leg hosted by team from the East Region) reversed from the previous season's final.Al-Hilal won 3–0 on aggregate.