| German Championship | 2021/12/09 10:00 | Christoph Negritu v Seifert, Stefan | 6-2,4-6,5-6 |
| German Championship | 2021/12/08 09:00 | Seifert, Stefan v Torski, Osman | 6-1,6-3 |
| German Championship | 2020/12/10 10:30 | Seifert, Stefan v Walder, Jordi | 4-6,6-1,3-6 |
| German Championship | 2020/12/07 15:30 | Seifert, Stefan v Eisenzapf, David | 6-1,6-4 |
| DTB German Pro Series | 2020/06/26 09:30 | Tom Schonenberg v Seifert, Stefan | 6-4,6-2 |
| DTB German Pro Series | 2020/06/25 08:00 | Kai Wehnelt v Seifert, Stefan | 6-4,6-2 |
| DTB German Pro Series | 2020/06/23 08:00 | Marvin Moeller v Seifert, Stefan | 4-6,6-3,7-5 |
| ITF - M15 Oberhaching | 2020/02/20 11:00 | Jakub Paul v Seifert, Stefan | 6-4,6-7,6-4 |
| German Championship | 2021/12/09 10:00 | Milan Welte v Gelhardt, Luca | 4-6,6-3,6-6 |
| German Championship | 2021/12/08 09:00 | Tom Gentzsch v Gelhardt, Luca | 4-6,1-6 |
| Exo Tennis Germany Series | 2020/07/31 11:00 | Hazem Naw v Gelhardt, Luca | 4-6,7-5,6-1 |
| Exo Tennis Germany Series | 2020/07/30 10:30 | Gelhardt, Luca v Benjamin Hassan | 5-7,4-6 |
| Exo Tennis Germany Series | 2020/07/29 11:10 | Gelhardt, Luca v Haerteis, Johannes | 4-6,3-6 |
| Exo Tennis Germany Series | 2020/07/28 08:00 | Schmitz, Constantin v Gelhardt, Luca | 6-3,6-1 |
| Exo Tennis Germany Series | 2020/07/25 09:30 | Schmitz, Constantin v Gelhardt, Luca | 6-3,6-2 |
| Exo Tennis Germany Series | 2020/07/24 09:30 | Djonov, Christian v Gelhardt, Luca | 0-6,6-7 |