| K League 1 2020 Relegation - Appearances as Assistant | ||||
| 04/10/2020 | FC Seoul | - | Busan IPark | 1:2 |
| 23/10/2020 | Suwon Bluewings | - | Seongnam FC | 1:2 |
| K League 1 2020 Relegation - Appearances as Assistant | ||||
| 04/10/2020 | FC Seoul | - | Busan IPark | 1:2 |
| 23/10/2020 | Suwon Bluewings | - | Seongnam FC | 1:2 |
| Complete name: | Eun-seok Gu |
| Born: | |
| Place of birth: |
South Korea |
| Nationality: |
South Korea |