| US Open | 2018/06/14 00:20 | Sitthikom Thammasin v Mark Caljouw | L | 0-2 |
| Giraldilla Int. XD | 2018/04/05 04:40 | Minoru Koga v Sitthikom Thammasin | L | 2-0 |
| Giraldilla Int. XD | 2018/02/21 09:20 | Sitthikom Thammasin v Takuma Ueda | W | 2-1 |
| Giraldilla Int. XD | 2018/01/10 06:30 | Panji Ahmad Maulana v Sitthikom Thammasin | L | 2-0 |
| Macau Open | 2017/11/09 05:30 | Kuei Chun Shih v Sitthikom Thammasin | L | 2-1 |
| Macau Open | 2017/11/08 02:50 | Adulrach Namkul v Sitthikom Thammasin | W | 0-2 |
| Giraldilla Int. XD | 2017/10/29 06:00 | Shesar Hiren Rhustavito v Sitthikom Thammasin | L | 2-0 |
| Giraldilla Int. XD | 2017/10/28 08:00 | Sitthikom Thammasin v Adulrach Namkul | W | 2-0 |
| Giraldilla Int. XD | 2018/06/20 01:00 | Kevin Cordon v Kai Schaefer | W | 0-2 |
| US Open | 2018/06/13 23:40 | Xiaodong Sheng v Kai Schaefer | L | 2-1 |
| Indonesia Masters XD | 2018/05/23 03:00 | Wing Ki Vincent Wong v Kai Schaefer | L | 2-1 |
| Indonesia Masters XD | 2018/05/22 03:00 | Kenta Nishimoto v Kai Schaefer | L | 2-1 |
| Indonesia Masters XD | 2018/05/20 12:00 | Tien Chen Chou v Kai Schaefer | L | 2-0 |
| Indonesia Masters XD | 2018/04/24 09:00 | Jacob Nilsson v Kai Schaefer | L | 2-0 |
| Giraldilla Int. XD | 2018/04/06 07:30 | Kai Schaefer v Eetu Heino | L | 0-2 |
| Giraldilla Int. XD | 2018/03/28 13:50 | Kai Schaefer v R. M. V. Gurusaidutt | L | 0-2 |