| Italian Int. Qual | 2021/12/16 14:00 | Kian-Yu Oei v Nicolas A. Mueller | W | 1-2 |
| Lithuanian Int. | 2023/06/10 14:30 | Nicolas A. Mueller v Brian Holtschke | W | 2-0 |
| Lithuanian Int. | 2023/06/10 09:05 | Nicolas A. Mueller v Iikka Heino | W | 2-1 |
| Austrian Open Qual | 2023/05/25 11:05 | Nicolas A. Mueller v Eogene Ewe | L | 0-2 |
| Swedish Open Qual | 2023/05/11 19:15 | Panji Ahmad Maulana v Nicolas A. Mueller | L | 2-0 |
| Swedish Open Qual | 2023/05/11 15:45 | Nicolas A. Mueller v Albin Carl Hjelm | W | 2-0 |
| Swedish Open Qual | 2023/05/11 09:55 | Mykhailo Vyshnevyi v Nicolas A. Mueller | W | 0-2 |
| Luxembourg Open Qual | 2023/05/04 09:30 | Yu Huang v Nicolas A. Mueller | L | 2-0 |
| Swiss Open Qual | 2023/03/21 10:40 | Joran Kweekel v Nicolas A. Mueller | L | 2-0 |
| Lithuanian Int. | 2023/06/10 15:30 | Kian-Yu Oei v Henrikho Kho Wibowo | W | 2-0 |
| Lithuanian Int. | 2023/06/10 09:20 | Prahdiska B Shujiwo v Kian-Yu Oei | W | 1-2 |
| Bonn Int. | 2023/06/01 12:40 | Kian-Yu Oei v Kuan Lin Kuo | L | 1-2 |
| Austrian Open Qual | 2023/05/25 09:00 | Kian-Yu Oei v Chong King Lim | L | 0-2 |
| Slovenia Open Quals | 2023/05/18 08:40 | Dicky Dwi Pangestu v Kian-Yu Oei | L | 2-1 |
| Slovenia Open Quals | 2023/05/17 17:55 | Kian-Yu Oei v Marton Szerecz | W | 2-0 |
| Slovenia Open Quals | 2023/05/17 10:30 | Kian-Yu Oei v Daniel Dvorak | W | 2-0 |
| Luxembourg Open Qual | 2023/05/04 12:15 | Kian-Yu Oei v Dennis Koppen | L | 0-2 |