Stadion: Court 7 Round: 54 Ground: Clay
| ITF - M25 - Überlingen | 2021/08/19 10:00 | Niklas Schell v Eduard Esteve Lobato | 6-7,1-6 |
| ITF - M25 - Überlingen | 2021/08/18 09:30 | Niklas Schell v Florian Broska | 3-6,6-3,6-3 |
| ITF - M25 - Frankfurt am Main | 2021/08/10 10:30 | Taiyo Yamanaka v Niklas Schell | 6-1,6-2 |
| ITF - M25 - Frankfurt am Main | 2021/08/09 11:55 | Max Wiskandt v Niklas Schell | 6-3,3-6,5-10 |
| ITF - M25 - Marburg | 2021/07/07 13:00 | Louis Wessels v Niklas Schell | 6-3,6-4 |
| ITF - M25 - Klosters | 2021/06/20 08:55 | Ilias Zimmermann v Niklas Schell | 6-4,4-6,12-10 |
| ITF - M15 - Antalya | 2021/05/23 07:00 | Niklas Schell v Stefano D'Agostino | 4-6,6-3,7-10 |
| ITF - M15 - Troisdorf | 2021/05/09 08:00 | Marlon Vankan v Niklas Schell | 2-6,7-6,13-11 |
| ITF - M15 - Huy | 2021/08/22 17:00 | John Sperle v Nicolas Bruna | 6-4,6-7,8-10 |
| ITF - M25 - Koksijde | 2021/08/19 08:00 | John Sperle v Simon Carr | 2-6,2-6 |
| ITF - M25 - Koksijde | 2021/08/16 08:00 | Victor Ernaelsteen v John Sperle | 3-6,3-6 |
| ITF - M25 - Wetzlar | 2021/08/03 15:30 | John Sperle v Osman Torski | 3-6,3-6 |
| UTR Pro Tennis Series - Mülheim | 2021/07/30 13:30 | Hazem Naw v John Sperle | 6-4,6-2 |
| UTR Pro Tennis Series - Mülheim | 2021/07/30 07:00 | Hendrik Jebens v John Sperle | 4-6,6-7 |
| UTR Pro Tennis Series - Mülheim | 2021/07/29 08:30 | Marvin Schaber v John Sperle | 2-6,2-6 |
| UTR Pro Tennis Series - Mülheim | 2021/07/28 12:00 | Tim Gennes v John Sperle | 1-6,3-6 |