Stadium: Center Court Round: 29 Ground: Clay
| ITF M25 Wetzlar | 2021/08/07 11:00 | David Pichler v Peter Heller | 3-6,7-5,3-6 |
| ITF M25 Wetzlar | 2021/08/06 15:55 | Constantin Schmitz v Peter Heller | 3-6,7-5,1-6 |
| ITF M25 Wetzlar | 2021/08/05 09:00 | Georgii Kravchenko v Peter Heller | 6-7,2-6 |
| ITF M25 Wetzlar | 2021/08/04 08:00 | Marvin Moeller v Peter Heller | 2-6,3-6 |
| Challenger Salzburg | 2021/07/08 10:30 | Nicolas Jarry v Peter Heller | 6-2,6-4 |
| Challenger Salzburg | 2021/07/05 10:35 | Francisco Cerundolo v Peter Heller | 3-6,6-3,3-6 |
| ITF M15 Antalya | 2021/05/06 08:10 | Nick Hardt v Peter Heller | 3-6,6-0,7-5 |
| ITF M15 Antalya | 2021/05/05 08:55 | Karl Friberg v Peter Heller | 3-6,3-6 |
| ITF M25 Wetzlar | 2021/08/07 14:10 | Harold Mayot v Christopher Heyman | 3-6,6-7 |
| ITF M25 Wetzlar | 2021/08/06 12:00 | Christopher Heyman v Alexey Vatutin | 6-3,7-5 |
| ITF M25 Wetzlar | 2021/08/05 11:35 | Christopher Heyman v Mats Rosenkranz | 6-4,7-6 |
| ITF M25 Wetzlar | 2021/08/04 08:00 | Christopher Heyman v Gauthier Onclin | 6-3,6-2 |
| Challenger Poznan | 2021/07/26 10:00 | Elmar Ejupovic v Christopher Heyman | 7-6,6-2 |
| Challenger Poznan | 2021/07/25 13:00 | Maks Kasnikowski v Christopher Heyman | 3-6,4-6 |
| ITF M25 Marburg | 2021/07/07 14:55 | Christopher Heyman v Henri Squire | 5-7,3-6 |
| ITF M25 The Hague | 2021/07/02 14:30 | Jelle Sels v Christopher Heyman | 6-3,6-0 |