Estadio: Court 2 Round: 19 Ground: Clay
| Challenger de Lille | 2021/03/23 10:45 | Matteo Martineau v Nicola Kuhn | 3-6,2-6 |
| Challenger de Szczecin | 2021/09/12 14:35 | Nicola Kuhn v Nathaniel Lammons | 6-3,6-4 |
| Challenger de Sevilla | 2021/09/07 10:50 | Gian Marco Moroni v Nicola Kuhn | 7-6,6-1 |
| Challenger de Meerbusch | 2021/08/10 08:30 | Nicola Kuhn v Nick Hardt | 6-4,6-3 |
| ATP Hamburgo | 2021/07/12 10:30 | Nicola Kuhn v Thiago Seyboth Wild | 6-1,1-6,2-6 |
| Challenger de Braunschweig | 2021/07/07 11:40 | Nicola Kuhn v Henri Laaksonen | 4-6,5-7 |
| Challenger de Braunschweig | 2021/07/06 15:25 | Nicola Kuhn v Mischa Zverev | 6-2,7-6 |
| Challenger de Porto | 2021/06/29 12:50 | Nicola Kuhn v Emilio Gomez | 5-7,2-6 |
| ATP Mallorca | 2021/06/21 17:10 | Nicola Kuhn v Feliciano Lopez | 1-6,6-7 |
| Challenger de Tulln | 2021/09/07 08:00 | Matteo Martineau v Jonas Forejtek | 2-6,6-7 |
| Challenger de Tulln | 2021/09/06 08:00 | Matteo Martineau v Mate Valkusz | 7-5,1-6,6-4 |
| Challenger de Tulln | 2021/09/05 09:00 | Matteo Martineau v Lenny Hampel | 6-3,6-2 |
| ITF M25 Lesa | 2021/08/29 14:50 | Alessandro Bega v Matteo Martineau | 5-7,6-2,2-6 |
| ITF M25 Lesa | 2021/08/27 19:00 | Jean Thirouin v Matteo Martineau | 1-6,1-6 |
| ITF M25 Lesa | 2021/08/26 10:30 | Andrea Basso v Matteo Martineau | 3-6,2-6 |
| ITF M25 Lesa | 2021/08/25 12:15 | Pietro Marino v Matteo Martineau | 1-6,4-6 |
| Challenger de Luedenscheid | 2021/08/19 11:15 | Matteo Martineau v Camilo Ugo Carabelli | 4-6,6-7 |