Stadium: Ochsenhausen, Germany
| Challenger - Series TT | 2023/11/13 07:30 | Dennis Klein v Sven Happek | L | 3-0 |
| Challenger - Series TT | 2023/06/22 14:30 | Dennis Klein v Sven Happek | L | 3-0 |
| Challenger - Series TT | 2023/06/19 09:10 | Dennis Klein v Sven Happek | L | 3-1 |
| Challenger - Series TT | 2023/05/08 17:10 | Sven Happek v Dennis Klein | L | 1-3 |
| Challenger - Series TT | 2023/04/03 12:30 | Dennis Klein v Sven Happek | L | 3-1 |
| Challenger - Series TT | 2023/03/06 19:30 | Sven Happek v Dennis Klein | L | 1-3 |
| Challenger - Series TT | 2023/01/23 07:30 | Sven Happek v Dennis Klein | L | 1-3 |
| Challenger - Series TT | 2023/01/09 14:10 | Sven Happek v Dennis Klein | L | 0-3 |
| Challenger - Series TT | 2024/01/15 10:10 | Hannes Hormann v Sven Happek | L | 3-1 |
| Challenger - Series TT | 2024/01/15 08:10 | Sven Happek v Francesco Maragioglio | W | 3-0 |
| Challenger - Series TT | 2024/01/09 10:10 | Sven Happek v Reda Nemras | W | 3-0 |
| Challenger - Series TT | 2024/01/08 20:50 | Sven Happek v Takumi Kageyama | L | 0-3 |
| Challenger - Series TT | 2024/01/08 18:10 | Sven Happek v Hannes Hormann | L | 1-3 |
| Challenger - Series TT | 2024/01/08 15:30 | Jeromy Loffler v Sven Happek | L | 3-0 |
| Challenger - Series TT | 2024/01/08 12:50 | Tobias Slanina v Sven Happek | L | 3-0 |
| Challenger - Series TT | 2024/01/08 10:50 | Sven Happek v Bohdan Sinkevych | W | 3-2 |
| Challenger - Series TT | 2024/01/15 12:10 | Norbert Tauler v Dennis Klein | W | 1-3 |
| Challenger - Series TT | 2024/01/15 07:30 | Hannes Hormann v Dennis Klein | W | 1-3 |
| Challenger - Series TT | 2023/12/19 11:00 | Benjamin Fruchart v Dennis Klein | L | 3-2 |
| Challenger - Series TT | 2023/12/19 09:30 | Akito Itagaki v Dennis Klein | W | 0-3 |
| Challenger - Series TT | 2023/12/19 08:10 | Adrien Coton v Dennis Klein | W | 0-3 |
| Challenger - Series TT | 2023/12/18 18:10 | Damian Zech v Dennis Klein | W | 0-3 |
| Challenger - Series TT | 2023/12/18 16:10 | Benjamin Fruchart v Dennis Klein | L | 3-2 |
| Challenger - Series TT | 2023/12/18 13:30 | Liang Qiu v Dennis Klein | L | 3-1 |