Stadium: Kvarner 5 Round: 60 Ground: Clay
| 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 Croatia F2 | 2018/03/13 08:00 | Kai Lemstra v Valentin Royer | 1-6,6-4,6-3 |
| ITF Croatia F2 | 2018/03/11 08:00 | Kai Lemstra v Marco De Rosa | 6-2,6-3 |
| ITF Croatia F1 | 2018/03/07 09:00 | Anze Arh v Kai Lemstra | 7-5,6-1 |
| ITF Germany F3 Qual | 2018/01/29 16:30 | Dominik Boehler v Kai Lemstra | 7-6,7-6 |
| ITF Germany F3 Qual | 2018/01/28 17:00 | Charley Emhardt v Kai Lemstra | 1-6,2-6 |
| ITF Croatia F3 | 2018/03/19 09:00 | David Martirosian v Marcell Bartakovics | 2-6,2-6 |
| ITF Czech Republic F11 Qual | 2017/11/19 13:00 | Alessandro Ricci v Marcell Bartakovics | 7-6,7-6 |
| ITF Hungary F8 | 2017/09/06 11:30 | Zdenek Kolar v Marcell Bartakovics | 6-0,6-2 |
| ITF Hungary F8 | 2017/09/05 14:25 | Alexander Shevchenko v Marcell Bartakovics | 2-6,2-6 |
| ITF Hungary F8 Qual | 2017/09/04 09:00 | Daniel Kopeinigg v Marcell Bartakovics | 4-6,4-6 |
| ITF Hungary F8 Qual | 2017/09/03 07:30 | Patrik Jancovic v Marcell Bartakovics | 4-6,3-6 |
| ITF Hungary F7 | 2017/08/29 08:00 | Milan Drinic v Marcell Bartakovics | 6-2,1-6,7-6 |
| ITF Hungary F6 Qual | 2017/08/21 09:55 | Laszlo Szendroi v Marcell Bartakovics | 6-1,1-6,6-4 |