Stadium: C Round: 28
| ITF Portugal F11 | 2016/09/28 13:35 | Mertens, Yannick v Monteiro, Joao | 6-3,6-4 |
| ITF Portugal F20 | 2017/09/27 13:00 | Monteiro, Joao v Artunedo Martinav. | 7-5,7-5 |
| ITF Portugal F20 | 2017/09/26 14:40 | Monteiro, Joao v Walkow, Szymon | 6-3,6-2 |
| ITF Portugal F19 | 2017/09/23 11:20 | Monteiro, Joao v Gil, Fred | 4-6,2-6 |
| ITF Portugal F19 | 2017/09/22 13:45 | Monteiro, Joao v Jandric, Darko | 6-1,6-2 |
| ITF Portugal F19 | 2017/09/21 10:00 | Monteiro, Joao v Voljacques, Hugo | 6-3,7-6 |
| Challenger Alphen | 2017/09/06 10:00 | Monteiro, Joao v Moraing, Mats | 3-6,0-6 |
| ITF Portugal F18 | 2017/08/31 12:30 | Artunedo Martinav. v Monteiro, Joao | 3-6,6-3,6-4 |
| ITF Portugal F18 | 2017/08/30 13:00 | Rodrigues, Daniel v Monteiro, Joao | 1-6,1-6 |
| ITF Portugal F20 | 2017/09/28 12:10 | Daniel Masur v Mertens, Yannick | 2-6,6-7 |
| ITF Portugal F20 | 2017/09/27 11:25 | Hubert Hurkacz v Mertens, Yannick | 4-6,1-6 |
| ITF Portugal F20 | 2017/09/26 09:00 | Kanar, Jonathan v Mertens, Yannick | 3-6,0-6 |
| ATP Metz Qual | 2017/09/18 11:30 | Gojowczyk, Peter v Mertens, Yannick | 6-3,6-4 |
| ATP Metz Qual | 2017/09/17 13:50 | Mertens, Yannick v Calvin Hemery | 7-5,6-1 |
| Istanbul, Turkey | 2017/09/12 11:15 | Mirza Basic v Mertens, Yannick | 3-6,6-3,7-5 |
| Challenger Istanbul Qual | 2017/09/10 08:00 | Mertens, Yannick v Dzhanashia, Shalva | 6-1,6-2 |
| Challenger Istanbul Qual | 2017/09/09 09:25 | Mertens, Yannick v Strokan, Artem | 6-0,6-0 |