Stadium: Court 3 Round: 166 Ground: Hardcourt outdoor
| Challenger Noumea | 2018/12/31 04:05 | Daniel Masur v Nielsen, Frederik | 6-1,5-7,6-4 |
| Challenger Fairfield | 2018/10/08 17:00 | King, Kevin v Nielsen, Frederik | 6-4,6-3 |
| Challenger Fairfield | 2018/10/07 18:15 | Thai-Son Kwiatkowski v Nielsen, Frederik | 7-6,3-6,5-7 |
| Challenger Fairfield | 2018/10/06 22:15 | Nielsen, Frederik v Ortega-Olmedo, Roberto | 6-2,6-2 |
| Challenger Stockton | 2018/09/29 23:05 | Alexander Ritschard v Nielsen, Frederik | 6-4,7-6 |
| Challenger Tiburon | 2018/09/22 18:15 | Nielsen, Frederik v Sarkissian, Alexander | 4-6,5-7 |
| Challenger Cary | 2018/09/08 18:20 | Nielsen, Frederik v Song, Evan | 2-6,6-7 |
| Challenger Chicago | 2018/09/02 22:00 | Kaichi Uchida v Nielsen, Frederik | 6-3,6-4 |
| Challenger Canberra | 2019/01/06 23:00 | Martin, Fabrice v Chun Hsin Tseng | 3-6,6-7 |
| Challenger Canberra | 2019/01/05 23:00 | Martin, Fabrice v Radojkovic, Milan | 6-1,6-4 |
| Mouilleron-Le-Captif, France | 2018/11/05 13:40 | Martin, Fabrice v Alexandre Muller | 4-6,4-6 |
| Mouilleron-Le-Captif, France | 2018/11/04 13:10 | Martin, Fabrice v Dan Added | 6-2,6-4 |
| Mouilleron-Le-Captif, France | 2018/11/03 16:00 | Oscar Otte v Martin, Fabrice | 6-7,6-7 |
| Vancouver, Canada | 2018/08/11 19:40 | Torpegaard, Mikael v Martin, Fabrice | 6-4,3-6,6-3 |
| Challenger Bordeaux Qual | 2018/05/12 13:40 | Martin, Fabrice v Pontico, Hugo | 6-4,4-6,3-6 |
| ATP Sydney Qual | 2018/01/06 01:30 | Martin, Fabrice v Safranek, Vaclav | 1-6,2-6 |