| Yellow | VS Club | Date | Sections | |
|---|---|---|---|---|
| 6 | AEK Athens | 28-08-2018 | Play-Off Round | Match details |
| 5 | F91 Dudelange | 17-07-2018 | First Round | Match details |
| 4 | Ludogorets Razgrad | 01-08-2018 | Second Round | Match details |
| 4 | Ludogorets Razgrad | 25-07-2018 | Second Round | Match details |
| 3 | Malmo FF | 14-08-2018 | Third Round | Match details |
| 2 | AEK Athens | 22-08-2018 | Play-Off Round | Match details |
