| US Open | 2023/07/12 19:10 | Kai Schaefer v Koo Takahashi | L | 0-2 |
| Canada Open Qual | 2023/07/04 16:55 | Kai Schaefer v Parupalli Kashyap | L | 0-2 |
| European Games | 2023/06/28 08:30 | Luka Wraber v Kai Schaefer | W | 1-2 |
| Thailand Open Qual | 2023/05/30 06:55 | Chia Hao Lee v Kai Schaefer | L | 2-1 |
| Malaysia Masters Qual | 2023/05/23 02:00 | Christian Adinata v Kai Schaefer | L | 2-0 |
| Sudirman Cup | 2023/05/15 02:20 | Kunlavut Vitidsarn v Kai Schaefer | L | 2-0 |
| Orleans Masters | 2023/04/05 12:40 | Lanxi Lei v Kai Schaefer | L | 2-0 |
| Spain Masters Qual | 2023/03/28 08:40 | Christian Adinata v Kai Schaefer | L | 2-0 |