| ITF Czech Republic F3 Qual | 2018/05/28 08:00 | Kai Lemstra v Dominik Recek | 2-6,2-6 |
| ITF Czech Republic F2 | 2018/05/22 08:00 | Kai Lemstra v Bart Van Den Berg | 3-6,3-6 |
| ITF Croatia F3 | 2018/03/22 11:30 | Kai Lemstra v Deni Zmak | 6-4,1-6,4-6 |
| ITF Croatia F3 | 2018/03/21 15:05 | Kai Lemstra v Xin Hu | 6-2,6-1 |
| ITF Croatia F3 | 2018/03/20 09:00 | Kai Lemstra v Marcell Bartakovics | 6-0,3-6,6-1 |
| ITF Croatia F3 | 2018/03/19 12:30 | Kai Lemstra v Edoardo Pompei | 6-1,2-6,7-6 |
| ITF Croatia F3 | 2018/03/19 09:00 | Kai Lemstra v Michelangelo Endrizzi | 6-3,6-4 |
| ITF Croatia F2 | 2018/03/14 09:00 | Kai Lemstra v Bruno Santanna | 3-6,3-6 |
| ITF Germany F7 | 2018/07/08 15:30 | Maximilien Sanson v Tim Handel | 2-6,1-6 |
| ITF Germany F11 | 2015/08/09 12:00 | Prajnesh Gunneswaran v Tim Handel | 6-1,6-3 |
| ITF Germany F1 Qual | 2015/01/04 09:00 | Philipp Schroll v Tim Handel | 7-6,7-5 |