Stadium: Court 18 Round: 25 Ground: Clay
| ITF Germany F13 | 2018/08/20 09:00 | Kai Lemstra v Jordi Walder | 3-6,6-1,3-6 |
| Challenger Augsburg | 2019/08/05 12:25 | Facundo Mena v Kai Lemstra | 6-4,6-2 |
| ITF M15 Bad Schussenried | 2019/07/23 14:35 | Nik Razborsek v Kai Lemstra | 6-2,6-3 |
| ITF M15 Bad Schussenried | 2019/07/22 13:00 | Roy Sarut De Valk v Kai Lemstra | 5-7,4-6 |
| ITF M15 Bad Schussenried | 2019/07/22 08:00 | Giordan Kunz v Kai Lemstra | 1-6,1-6 |
| ITF M15 Kramsach | 2019/07/17 09:00 | Kai Lemstra v Bart Van Den Berg | 4-6,2-6 |
| ITF M15 Kramsach | 2019/07/15 13:30 | Kai Lemstra v Evzen Holis | 6-3,4-6,10-6 |
| ITF M15 Troisdorf | 2019/05/06 14:00 | Mick Veldheer v Kai Lemstra | 2-6,6-1,10-7 |
| ITF M15 Sharm El Sheikh | 2019/03/21 08:00 | Enrico Dalla Valle v Kai Lemstra | 6-1,6-1 |
| ITF M15 Marburg | 2019/07/08 08:00 | Tim Heger v Jordi Walder | 3-6,7-5,10-7 |
| ITF M15 Kamen | 2019/06/26 09:00 | Sebastian Prechtel v Jordi Walder | 6-4,3-6,6-3 |
| ITF M15 Kamen | 2019/06/24 12:30 | Ewan Moore v Jordi Walder | 6-4,3-6,6-10 |
| ITF M15 Kamen | 2019/06/24 08:00 | Daniel Litvinov v Jordi Walder | 1-6,2-6 |
| ITF M15 Kaltenkirchen | 2019/06/10 08:00 | Paul Woerner v Jordi Walder | 6-3,6-3 |
| ITF M15 Troisdorf | 2019/05/06 10:00 | Kacper Zuk v Jordi Walder | 6-0,6-3 |
| ITF M15 Troisdorf | 2019/05/06 07:00 | Daniil Strelchenko v Jordi Walder | 2-6,1-6 |
| ITF M15 Antalya | 2019/04/29 06:45 | Jordi Walder v Michalis Sakellaridis | 3-6,3-6 |