Stadium: Court 3 Round: 62 Ground: Clay
| ITF M15 Monastir | 2021/05/09 11:00 | Taisei Ichikawa v Niklas Waldner | 6-1,6-0 |
| ITF M15 Monastir | 2021/05/02 12:00 | Andrea Picchione v Niklas Waldner | 6-2,6-4 |
| ITF M15 Monastir | 2021/04/25 11:30 | Niklas Waldner v Iiro Vasa | 1-6,4-6 |
| ITF M15 Anif | 2020/08/23 07:00 | Davide Galoppini v Niklas Waldner | 6-3,6-4 |
| ITF M25 Vogau | 2020/08/17 11:30 | Niklas Waldner v Alexander Shevchenko | 4-6,2-6 |
| ITF M25 Vogau | 2020/08/17 07:30 | Dean Thurner v Niklas Waldner | 4-6,6-2,5-10 |
| Austrian Tennis Championship | 2020/07/28 12:00 | Lucas Miedler v Niklas Waldner | 6-3,6-2 |
| Austrian Tennis Championship | 2020/07/27 10:00 | David Pichler v Niklas Waldner | 6-0,6-0 |
| ITF M25 Prague | 2021/05/10 10:30 | Milos Karol v Lucas Bouquet | 6-4,3-6,5-10 |
| ITF M25 Prague | 2021/05/09 13:30 | Nicolas Alvarez v Milos Karol | 3-6,4-6 |
| ITF M15 Bratislava | 2021/03/10 11:40 | Milos Karol v Jonathan Eysseric | 6-7,4-6 |
| ITF M15 Bratislava | 2021/03/09 09:00 | Samo Polakovic v Milos Karol | 4-6,1-6 |
| ITF M15 Bratislava | 2021/03/08 12:00 | Milos Karol v Nikolas Lahky | 6-3,6-2 |
| ITF M15 Bratislava | 2021/03/02 09:00 | Peter Nad v Milos Karol | 6-3,6-3 |
| ITF M15 Bratislava | 2021/03/01 09:00 | Milos Karol v Edward Hubner | 7-6,6-4 |
| ITF M15 Bratislava | 2020/11/24 09:00 | Filip Misolic v Milos Karol | 6-1,6-2 |