| UTR Pro Tennis Series Dubai | 2022/01/07 04:30 | Michael Zhu v Kai Lemstra | 7-6,6-2 |
| UTR Pro Tennis Series Dubai | 2022/01/06 06:00 | David Pichler v Kai Lemstra | 6-4,4-6,4-6 |
| UTR Pro Tennis Series Dubai | 2022/01/05 07:30 | Mircea-Alexandru Jecan v Kai Lemstra | 6-4,7-5 |
| UTR Pro Tennis Series Dubai | 2022/01/03 10:50 | Jonathan Eysseric v Kai Lemstra | 6-3,6-1 |
| German Championship | 2021/12/07 15:00 | Kai Lemstra v Tom Schonenberg | 3-6,0-6 |
| ITF M15 Heraklion | 2021/11/23 07:00 | Nicholas David Ionel v Kai Lemstra | 3-6,7-5,10-4 |
| ITF M15 Heraklion | 2021/11/22 08:00 | Sergis Kyratzis v Kai Lemstra | 4-6,2-6 |
| ITF M15 Heraklion | 2021/11/21 07:00 | Liam Puttergill v Kai Lemstra | 2-6,1-6 |
| UTR Pro Tennis Series Dubai | 2022/01/07 07:30 | Martins Podzus v Simon Roberts | 6-3,6-0 |
| UTR Pro Tennis Series Dubai | 2022/01/05 04:30 | Oscar Jose Gutierrez v Simon Roberts | 6-4,6-1 |
| UTR Pro Tennis Series Dubai | 2022/01/03 06:00 | Igor Sijsling v Simon Roberts | 6-3,6-1 |
| Tie Break Tens Dubai | 2021/10/22 15:36 | Taylor Fritz v Simon Roberts | 1-0 |