| Champions League Qual. 2023/2024 - Appearances as Assistant | ||||
| 25/07/2023 | HJK Helsinki | - | Molde FK | 1:0 |
| 02/08/2023 | Qarabağ FK | - | Raków Częstochowa | 1:1 |
| Champions League Qual. 2023/2024 - Appearances as Assistant | ||||
| 25/07/2023 | HJK Helsinki | - | Molde FK | 1:0 |
| 02/08/2023 | Qarabağ FK | - | Raków Częstochowa | 1:1 |
| Complete name: | Lasse Koslowski |
| Born: | 14/07/1987 |
| Place of birth: |
Berlin, 
Germany |
| Residence: | Berlin |
| Nationality: |
Germany |
| Profession: | selbständig |
| Club: | Frohnauer SC |