Stadium: Court 2 Round: 62 Ground: Clay
| ITF Germany F10 Qual | 2018/07/29 15:30 | Nico Mertens v Niklas Koch | 6-4,7-6 |
| ITF Germany F9 | 2018/07/24 10:00 | Nico Mertens v Manuel Guinard | 0-6,6-4,4-6 |
| ITF Bosnia and Herzegovina F3 | 2018/05/29 10:40 | Nico Mertens v Nerman Fatic | 4-6,3-6 |
| ITF Czech Republic F2 Qual | 2018/05/21 08:00 | Nico Mertens v Michal Franek | 3-6,2-6 |
| ITF Czech Republic F2 Qual | 2018/05/20 08:00 | Nico Mertens v Radek Cyprich | 6-2,6-2 |
| ITF Tunisia F11 | 2018/03/19 08:30 | Nico Mertens v Jordi Munoz-Abreu | 1-6,3-6 |
| ITF Tunisia F11 | 2018/03/18 10:30 | Nico Mertens v Stefano Battaglino | 7-6,6-1 |
| ITF Tunisia F11 | 2018/03/17 08:00 | Nico Mertens v Miles Jones | 3-6,6-2,6-3 |
| ITF Germany F10 Qual | 2018/07/29 15:30 | Osni Junior v Leon Hoeveler | 6-2,7-6 |
| ITF Germany F10 Qual | 2018/07/29 08:00 | Osni Junior v Benedict Moerl | 6-2,4-6,6-2 |
| Challenger Rio De Janeiro Qual | 2017/11/18 14:15 | Fernando Romboli v Osni Junior | 4-6,7-5,6-3 |
| Challenger Campinas Qual | 2016/10/01 14:20 | Alex Blumenberg v Osni Junior | 6-1,6-2 |
| Challenger Santos | 2016/09/21 14:00 | Osni Junior v Thiago Monteiro | 2-6,6-7 |
| ITF Brazil F4 Qual | 2016/07/17 14:30 | Felipe Meligeni Rodrigues Alves v Osni Junior | 7-5,6-3 |
| ITF Brazil F4 Qual | 2016/07/17 12:00 | Osni Junior v Gabriel P Tumasonis | 6-3,6-2 |
| ITF Brazil F4 Qual | 2016/07/16 12:00 | Osni Junior v Gabriel Ciro Da Silva | 7-6,6-3 |