Stadium: Clay 8 Round: 62 Ground: Hardcourt outdoor
| ITF Netherlands F5 | 2018/08/19 10:00 | Niklas Guttau v Esteban Bruna | 3-6,4-6 |
| ITF Netherlands F4 | 2018/08/11 09:00 | Alban Meuffels v Niklas Guttau | 6-3,6-4 |
| ITF Poland F6 | 2018/08/07 11:25 | Adrian Andrzejczuk v Niklas Guttau | 6-2,6-1 |
| ITF Poland F6 Qual | 2018/08/06 08:00 | Niklas Guttau v Krzysztof Mlazga | 6-2,6-4 |
| ITF Poland F6 Qual | 2018/08/05 09:30 | Niklas Guttau v Michele Lorenzo Iftimie | 5-7,6-2,6-3 |
| ATP Hamburg Qual | 2018/07/21 12:45 | Jozef Kovalík v Niklas Guttau | 6-0,6-1 |
| ITF Germany F8 Qual | 2018/07/16 10:30 | Tim Seibert v Niklas Guttau | 6-7,7-6,6-2 |
| ITF Germany F8 Qual | 2018/07/15 12:30 | Marcel Marlon Sudzum v Niklas Guttau | 4-6,0-6 |
| ITF Romania F13 | 2018/09/12 06:30 | Oleg Prihodko v Neil Oberleitner | 6-3,7-6 |
| ITF Romania F13 | 2018/09/10 07:00 | Mihai Razvan Marinescu v Neil Oberleitner | 3-6,4-6 |
| ITF Romania F13 | 2018/09/09 07:00 | Neil Oberleitner v Sorin Andrei Iordache | 6-7,6-2,6-3 |
| ITF Romania F12 | 2018/09/02 07:00 | Kenta Kurita v Neil Oberleitner | 7-5,7-5 |
| ITF Hungary F6 | 2018/08/21 11:30 | Neil Oberleitner v Pascal Meis | 1-6,2-6 |
| ITF Hungary F6 | 2018/08/19 11:00 | David Damian Brna v Neil Oberleitner | 4-6,1-6 |
| ITF Austria F6 | 2018/08/07 10:35 | Neil Oberleitner v Philipp Schroll | 3-6,4-6 |
| ITF Austria F6 | 2018/08/05 10:10 | Filippo Bettini v Neil Oberleitner | 2-6,2-6 |