Stadium: Court 1 Round: 25 Ground: Clay
| ITF M25 Caslano | 2021/08/26 14:30 | Giovanni Oradini v Tobias Simon | 4-6,6-4,3-6 |
| ITF M25 Caslano | 2021/08/25 13:10 | Stefano Baldoni v Tobias Simon | 6-7,1-6 |
| ITF M25 Frankfurt am Main | 2021/08/10 13:55 | Tobias Simon v Christian Sigsgaard | 3-6,3-6 |
| ITF M25 Bakio | 2021/06/29 13:00 | Pablo Llamas Ruiz v Tobias Simon | 7-5,6-2 |
| ITF M25 Klosters | 2021/06/24 08:35 | Dominic Stephan Stricker v Tobias Simon | 7-6,6-7,6-3 |
| ITF M25 Klosters | 2021/06/23 12:00 | Tomas Papik v Tobias Simon | 3-6,4-6 |
| Challenger Forli | 2021/06/14 09:30 | Thiago Agustin Tirante v Tobias Simon | 7-6,6-3 |
| Challenger Forli | 2021/06/13 14:15 | Matteo Arnaldi v Tobias Simon | 6-7,2-6 |
| ITF M25 Prostejov | 2021/08/16 11:15 | Zsombor Piros v Matthew William Donald | 6-3,6-4 |
| Challenger Liberec | 2021/08/01 14:00 | Matthew William Donald v Rudolf Molleker | 6-4,5-7,5-7 |
| ITF M25 Jablonec Nad Nisou | 2021/05/19 15:15 | Matthew William Donald v Manuel Guinard | 1-6,5-7 |
| ITF M25 Prague | 2021/05/09 12:30 | Matthew William Donald v Lenny Hampel | 2-6,6-4,8-10 |