Stadium: Court 1 Round: 19 Ground: Carpet indoor
| Challenger Bucharest | 2021/09/20 11:20 | Vitaliy Sachko v Alexander Erler | 6-2,6-2 |
| Challenger Tulln | 2021/09/06 12:10 | Alexander Erler v Lukas Rosol | 4-6,7-5,1-6 |
| Challenger Como | 2021/08/31 08:00 | Riccardo Bonadio v Alexander Erler | 3-6,6-3,6-3 |
| Challenger Como | 2021/08/30 09:00 | Filippo Baldi v Alexander Erler | 6-7,4-6 |
| Challenger Como | 2021/08/29 11:45 | Marcello Serafini v Alexander Erler | 1-6,6-3,6-7 |
| Challenger Warsaw | 2021/08/25 12:40 | Nicolas Kicker v Alexander Erler | 2-6,7-5,6-3 |
| ATP Kitzbuhel | 2021/07/28 14:50 | Mikael Ymer v Alexander Erler | 6-2,6-3 |
| ATP Kitzbuhel | 2021/07/27 15:00 | Alexander Erler v Carlos Alcaraz Garfia | 7-5,1-6,6-2 |
| ITF M25 Skopje | 2021/09/29 07:30 | Henri Squire v Eric Vanshelboim | 6-2,6-3 |
| ITF M25 Pardubice | 2021/09/26 08:00 | Filip Misolic v Henri Squire | 7-5,6-3 |
| ITF M25 Pardubice | 2021/09/25 09:40 | Henri Squire v Alexander Weis | 6-4,6-1 |
| ITF M25 Pardubice | 2021/09/24 11:00 | Henri Squire v Pavel Nejedly | 6-1,6-3 |
| ITF M25 Pardubice | 2021/09/23 11:15 | Milos Karol v Henri Squire | 1-6,1-6 |
| ITF M25 Pardubice | 2021/09/22 10:50 | Matvey Minin v Henri Squire | 6-3,3-6,4-6 |
| ITF M15 Allershausen | 2021/09/01 11:15 | Peter Heller v Henri Squire | 6-3,3-6,6-4 |
| ITF M25 Trier | 2021/08/28 12:40 | Louis Wessels v Henri Squire | 7-5,5-7,6-3 |