Stadium: Center Court Round: 26 Ground: Carpet indoor
| ITF M25 Hamburg | 2021/10/23 10:00 | Henri Squire v Johannes Haerteis | 6-4,6-4 |
| ITF M25 Hamburg | 2021/10/22 12:10 | Johannes Haerteis v Daniel Little | 6-4,6-4 |
| ITF M25 Hamburg | 2021/10/21 15:45 | Johannes Haerteis v Leonard Von Hindte | 6-3,6-4 |
| ITF M25 Hamburg | 2021/10/20 10:50 | Johannes Haerteis v Riccardo Balzerani | 6-3,6-4 |
| ITF M25 Jonkoping | 2021/09/20 10:45 | Filip Bergevi v Johannes Haerteis | 6-4,7-6 |
| ITF M25 Plaisir | 2021/09/15 11:45 | Johannes Haerteis v Leny Mitjana | 4-6,6-7 |
| Challenger Tulln | 2021/09/06 13:00 | Johannes Haerteis v Filip Horansky | 6-4,4-6,3-6 |
| Challenger Mallorca | 2021/09/01 18:40 | Johannes Haerteis v Lukas Lacko | 2-6,3-6 |
| Challenger Barcelona | 2021/10/05 08:00 | Dmitry Popko v Tristan Lamasine | 6-3,6-2 |
| Challenger Lisbon | 2021/09/28 10:55 | Frederico Ferreira Silva v Tristan Lamasine | 6-3,6-4 |
| Challenger Rennes | 2021/09/16 14:20 | Tristan Lamasine v Arthur Rinderknech | 6-7,2-6 |
| Challenger Rennes | 2021/09/13 12:50 | Go Soeda v Tristan Lamasine | 6-7,4-6 |
| Challenger Kyiv | 2021/09/08 10:35 | Tristan Lamasine v Franco Agamenone | 6-3,2-6,4-6 |
| Challenger Kyiv | 2021/09/06 09:35 | Tristan Lamasine v Kaichi Uchida | 7-6,6-2 |
| Challenger Como | 2021/08/31 08:00 | Juan Manuel Cerundolo v Tristan Lamasine | 6-4,7-6 |
| Challenger Warsaw | 2021/08/26 12:20 | Nino Serdarusic v Tristan Lamasine | 6-1,3-6,7-5 |