Stadium: Centre Court Round: 25 Ground: Clay
| ITF M25 - La Nucia | 2021/03/19 14:05 | Sebastian Fanselow v Raul Brancaccio | 6-7,0-6 |
| ITF M25 - Vale Do Lobo | 2021/03/14 11:30 | Kaichi Uchida v Sebastian Fanselow | 5-7,7-6,7-6 |
| ITF M25 - Vale Do Lobo | 2021/03/13 13:20 | Sebastian Fanselow v Tak Khunn Wang | 6-1,6-3 |
| ITF M25 - Vale Do Lobo | 2021/03/12 10:30 | Sebastian Fanselow v Pedro Araujo | 6-2,7-6 |
| ITF M25 - Vale Do Lobo | 2021/03/11 16:05 | Bradley Paliska v Sebastian Fanselow | 2-6,2-6 |
| ITF M25 - Vale Do Lobo | 2021/03/10 13:20 | Fabio Coelho v Sebastian Fanselow | 1-6,4-6 |
| ITF M25 - Faro | 2021/03/04 11:20 | Sebastian Fanselow v Tomas Lipovsek Puches | 3-6,6-3,6-7 |
| ITF M25 - Faro | 2021/03/03 09:30 | Sebastian Fanselow v Fabio Coelho | 6-2,6-3 |
| ITF M25 - Reus | 2021/04/15 10:05 | Titouan Droguet v Nikolas Sanchez Izquierdo | 6-4,6-3 |
| ITF M25 - Reus | 2021/04/13 10:45 | Kyrian Jacquet v Nikolas Sanchez Izquierdo | 4-6,4-6 |
| Challenger Marbella | 2021/03/30 14:45 | Damir Dzumhur v Nikolas Sanchez Izquierdo | 6-4,6-4 |
| Challenger Marbella | 2021/03/29 09:00 | Nikolas Sanchez Izquierdo v Timofey Skatov | 4-6,7-6,6-3 |
| Challenger Marbella | 2021/03/28 10:00 | Nikolas Sanchez Izquierdo v Angel G Melgar | 6-1,6-0 |
| Challenger Zadar | 2021/03/25 09:30 | Gianluca Mager v Nikolas Sanchez Izquierdo | 1-6,6-4,6-1 |
| Challenger Zadar | 2021/03/23 09:00 | Nikolas Sanchez Izquierdo v Matija Pecotic | 3-6,6-3,6-2 |
| Challenger Zadar | 2021/03/22 11:15 | Nikolas Sanchez Izquierdo v Skander Mansouri | 6-2,6-1 |