Stadium: C Round: 45 Ground: Hardcourt outdoor
| ITF Spain F18 | 2016/06/21 17:30 | Frederik Nielsen v Roberto Ortega-Olmedo | 4-6,6-1,5-7 |
| Challenger Cary | 2018/09/08 18:20 | Frederik Nielsen v Evan Song | 2-6,6-7 |
| Challenger Chicago | 2018/09/02 22:00 | Kaichi Uchida v Frederik Nielsen | 6-3,6-4 |
| Challenger Chicago | 2018/09/02 15:00 | Joris De Loore v Frederik Nielsen | 6-7,6-2,5-7 |
| Challenger Portoroz | 2018/08/07 08:00 | Lucas Miedler v Frederik Nielsen | 6-3,6-2 |
| Challenger Portoroz Qual | 2018/08/06 08:00 | Frederik Nielsen v Albano Olivetti | 6-2,7-6 |
| Challenger Portoroz Qual | 2018/08/05 08:00 | Andrea Pellegrino v Frederik Nielsen | 0-6,0-6 |
| Challenger Portoroz Qual | 2018/08/04 09:35 | Frederik Nielsen v Matic Dimic | 7-5,6-0 |
| Challenger Segovia Qual | 2018/07/29 14:30 | Karim-Mohamed Maamoun v Frederik Nielsen | 7-6,3-6,6-2 |
| Challenger Cary | 2018/09/11 21:10 | Roberto Ortega-Olmedo v Dominik Koepfer | 6-3,5-7,1-6 |
| Challenger Seville | 2018/09/03 08:30 | Alex Molcan v Roberto Ortega-Olmedo | 7-5,6-3 |
| Challenger Seville | 2018/09/01 18:30 | Thomas Statzberger v Roberto Ortega-Olmedo | 4-6,6-2,4-6 |
| Challenger Mallorca | 2018/08/29 12:25 | Roberto Ortega-Olmedo v Kenny de Schepper | 6-7,4-6 |
| Challenger Segovia | 2018/08/01 12:00 | Roberto Ortega-Olmedo v Ugo Humbert | 6-4,3-6,2-6 |
| Challenger Tampere | 2018/07/24 15:30 | Juan Ignacio Londero v Roberto Ortega-Olmedo | 6-1,7-5 |
| Challenger Astana | 2018/07/17 08:55 | Roberto Ortega-Olmedo v Pavel Kotov | 6-7,6-4,5-7 |
| ITF Spain F17 | 2018/07/06 13:00 | Denis Yevseyev v Roberto Ortega-Olmedo | 4-6,2-6 |