| ITF USA F30 | 2018/11/03 13:30 | Nikola Samardzic v Marcelo Sepulveda | 6-4,6-3 |
| Challenger Monterrey | 2018/09/29 20:35 | Marcelo Sepulveda v Emilio Nava | 4-6,4-6 |
| ITF USA F19 Qual | 2018/06/30 16:00 | Marcelo Sepulveda v Maxime Cressy | 4-6,2-6 |
| ITF Mexico F2 | 2018/05/15 17:25 | Marcelo Sepulveda v Samuel Shropshire | 3-6,2-6 |
| ITF Mexico F1 | 2018/05/06 16:00 | Alexander Merino v Marcelo Sepulveda | 6-2,5-7,6-3 |
| ITF Mexico F1 | 2018/05/05 16:00 | Marcelo Sepulveda v Conner McMann | 4-6,6-3,6-1 |
| Challenger Puerto Vallarta | 2018/05/01 00:45 | Marcelo Sepulveda v Santiago Giraldo | 2-6,0-6 |
| ITF USA F12 | 2018/04/22 17:00 | Marcelo Sepulveda v Julian Bradley | 6-7,7-6,3-6 |