Stadium: Pista 3 Round: 26 Ground: Clay
| ITF Portugal F8 | 2018/04/19 13:05 | Monteiro, Joao v Desein, Niels | 6-2,6-7,6-4 |
| ITF Spain F14 | 2018/06/05 11:55 | Monteiro, Joao v Fred Simonsson | 6-2,6-1 |
| Challenger Mestre | 2018/05/24 10:25 | Monteiro, Joao v Mitchell Krueger | 6-7,3-6 |
| Challenger Mestre | 2018/05/23 14:35 | Monteiro, Joao v Vilella Martinez, Mario | 7-5,6-7,6-1 |
| Lisbon, Portugal | 2018/05/15 13:10 | Taro Daniel v Monteiro, Joao | 7-6,7-6 |
| Challenger Braga | 2018/05/07 12:20 | Monteiro, Joao v Gleb Sakharov | 6-2,3-6,2-6 |
| ATP Estoril Qual | 2018/04/30 13:45 | Ojeda Lara, Ricardo v Monteiro, Joao | 6-3,2-6,6-3 |
| ATP Estoril Qual | 2018/04/29 12:35 | Monteiro, Joao v Robert, Stephane | 6-3,6-7,7-6 |
| ITF Portugal F8 | 2018/04/20 12:40 | Monteiro, Joao v Cacao, Tiago | 4-6,5-7 |
| ITF Spain F14 | 2018/06/05 09:30 | Desein, Niels v Cortes Alcaraz, Aaron | 6-4,7-6 |
| Challenger Bordeaux Qual | 2018/05/13 10:50 | Mathias Bourgue v Desein, Niels | 6-2,7-6 |
| Challenger Bordeaux Qual | 2018/05/12 11:10 | Eysseric, Jonathan v Desein, Niels | 3-6,6-3,3-6 |
| ITF France F8 | 2018/04/25 09:25 | Tristan Lamasine v Desein, Niels | 7-5,6-4 |
| ITF Portugal F8 | 2018/04/19 13:05 | Monteiro, Joao v Desein, Niels | 6-2,6-7,6-4 |
| ITF Portugal F8 | 2018/04/18 15:00 | Desein, Niels v Dias, Francisco | 6-1,4-6,6-1 |
| ITF Italy F7 | 2018/04/11 13:45 | Desein, Niels v Andrea Collarini | 3-6,6-7 |
| ITF Italy F7 | 2018/04/09 16:20 | Desein, Niels v Ornago, Fabrizio | 6-2,6-1 |