| K League 1 2019 Relegation - Appearances as Assistant | ||||
| 19/10/2019 | Sangju Sangmu | - | Jeju United | 2:1 |
| 30/11/2019 | Seongnam FC | - | Jeju United | 3:1 |
| K League 1 2019 Relegation - Appearances as Assistant | ||||
| 19/10/2019 | Sangju Sangmu | - | Jeju United | 2:1 |
| 30/11/2019 | Seongnam FC | - | Jeju United | 3:1 |
| Complete name: | Eun-seok Gu |
| Born: | |
| Place of birth: |
South Korea |
| Nationality: |
South Korea |