Stadium: Court 8 Round: 25 Ground: Hardcourt outdoor
| ITF Portugal F1 | 2018/02/24 13:05 | Mertens, Yannick v Cacao, Tiago | 3-6,6-4,4-6 |
| ITF Portugal F1 | 2018/02/23 11:25 | Mertens, Yannick v Ribeiro Marcondes, Igor | 3-6,6-4,6-1 |
| ITF Portugal F1 | 2018/02/22 15:05 | Mertens, Yannick v Fermosell, Jaime | 7-5,6-2 |
| ITF Portugal F1 | 2018/02/20 11:45 | Mertens, Yannick v Bogajo Fernandez, Fernando | 7-6,6-1 |
| ITF Great Britain F3 | 2018/02/13 12:15 | Evan Furness v Mertens, Yannick | 4-6,7-5,6-4 |
| ITF Great Britain F1 | 2018/02/04 11:00 | Griekspoor, Scott v Mertens, Yannick | 6-1,7-6 |
| ITF Great Britain F1 | 2018/02/03 10:00 | Mertens, Yannick v Viola, Matteo | 7-6,6-1 |
| ITF Great Britain F1 | 2018/02/02 10:00 | Pauffley, Neil v Mertens, Yannick | 6-7,4-6 |
| ITF Israel F1 | 2018/03/04 08:00 | Niklas-Salminen, Patrick v Kolobaev, Nikolay | 6-2,6-0 |
| ITF Israel F1 | 2018/03/03 10:30 | Niklas-Salminen, Patrick v George Goldhoff | 6-3,6-2 |
| ITF Turkey F3 | 2018/01/25 07:00 | Niklas-Salminen, Patrick v Gianluca Mager | 3-6,2-6 |
| ITF Turkey F3 | 2018/01/23 07:30 | Niklas-Salminen, Patrick v Shubladze, Vazha | 6-2,6-2 |
| ITF Turkey F3 | 2018/01/22 10:00 | Niklas-Salminen, Patrick v Alekseenko, Gleb | 6-0,6-0 |
| ITF Finland F4 | 2017/11/15 14:00 | Jomby, Tom v Niklas-Salminen, Patrick | 6-3,4-6,7-5 |
| ITF Finland F4 | 2017/11/14 19:55 | Niklas-Salminen, Patrick v Viola, Matteo | 6-4,3-6,7-5 |
| ITF Estonia F4 | 2017/11/07 09:00 | Niklas-Salminen, Patrick v Deviatiarov, Marat | 6-7,6-1,3-6 |