| 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 |
| ITF - M15 Héraklion | 2020/02/13 08:30 | Antonio Massara v Seifert, Stefan | 6-3,7-5 |
| ITF - M15 Héraklion | 2020/02/11 09:30 | Stamoulos, Ioannis v Seifert, Stefan | 0-6,6-2,3-6 |
| ITF - M15 Veigy-Foncenex | 2020/01/30 11:45 | Robert, Quentin v Seifert, Stefan | 7-6,4-6,6-3 |
| German Championship | 2020/12/08 16:40 | Max Hans Rehberg v Walder, Jordi | 6-7,4-5 |
| ITF M15 Trier | 2019/08/14 11:30 | Walder, Jordi v Obert, Adrian | 4-6,5-7 |
| ITF M15 Trier | 2019/08/13 11:05 | Kai Lemstra v Walder, Jordi | 4-6,2-6 |
| ITF M15 Marburg | 2019/07/08 08:00 | Heger, Tim v Walder, Jordi | 3-6,7-5,10-7 |
| ITF M15 Kamen | 2019/06/26 09:00 | Prechtel, Sebastian v Walder, Jordi | 6-4,3-6,6-3 |
| ITF M15 Kamen | 2019/06/24 12:30 | Ewan Moore v Walder, Jordi | 6-4,3-6,6-10 |
| ITF M15 Kamen | 2019/06/24 08:00 | Litvinov, Daniel v Walder, Jordi | 1-6,2-6 |
| Kaltenkirchen, Singles Qualifying M-ITF-GER-05A | 2019/06/10 08:00 | Paul Woerner v Walder, Jordi | 6-3,6-3 |