Stadium: Centre Court Round: 19 Ground: Clay
| Challenger Tulln | 2021/09/05 10:50 | Rudolf Molleker v Neil Oberleitner | 2-6,5-7 |
| ITF M15 Bad Waltersdorf | 2021/09/01 08:00 | Neil Oberleitner v Lorenzo Rottoli | 4-6,6-7 |
| ITF M15 Bad Waltersdorf | 2021/08/27 09:25 | Lukas Krainer v Neil Oberleitner | 6-7,6-4,6-0 |
| ITF M15 Bad Waltersdorf | 2021/08/26 06:55 | Neil Oberleitner v Eric Vanshelboim | 7-6,6-0 |
| ITF M15 Bad Waltersdorf | 2021/08/24 12:40 | Neil Oberleitner v Maximilian Homberg | 6-2,6-2 |
| ITF M15 Warmbad-Villach | 2021/08/19 10:15 | Jakob Aichhorn v Neil Oberleitner | 6-1,4-6,6-4 |
| ITF M15 Warmbad-Villach | 2021/08/18 10:05 | Neil Oberleitner v Savriyan Danilov | 7-5,7-6 |
| ITF M25 Frankfurt am Main | 2021/08/09 09:00 | Lenny Hampel v Neil Oberleitner | 6-4,6-4 |
| Challenger Tulln | 2021/09/05 10:40 | Pavel Nejedly v Gonzalo Villanueva | 2-6,4-6 |
| ITF M15 Zilina | 2021/09/01 12:25 | Gonzalo Villanueva v Peter Goldsteiner | 4-6,3-6 |
| ITF M25 Decatur | 2021/08/04 20:30 | Gonzalo Villanueva v Petros Chrysochos | 1-6,3-6 |
| Challenger Lexington | 2021/07/25 17:00 | Aidan Mchugh v Gonzalo Villanueva | 7-5,2-6,6-3 |
| Challenger Cary | 2021/07/20 15:00 | Roberto Cid Subervi v Gonzalo Villanueva | 3-6,7-5,6-1 |
| UTR Pro Tennis Series Atlanta | 2021/07/16 12:00 | Ivan Yatsuk v Gonzalo Villanueva | 6-1,6-4 |
| UTR Pro Tennis Series Atlanta | 2021/07/15 18:00 | William Mroz Mroz v Gonzalo Villanueva | 3-6,4-5 |
| UTR Pro Tennis Series Atlanta | 2021/07/12 13:30 | Vazha Shubladze v Gonzalo Villanueva | 6-1,6-2 |