Stadium: Court 2 Round: 25 Ground: Hardcourt indoor
| ITF - M15 Heraklion | 2020/11/17 08:30 | Petros Tsitsipas v Sebastian Fanselow | 2-6,3-6 |
| ITF - M25 Saint Dizier | 2021/11/03 13:20 | Petros Tsitsipas v Jeremy Jahn | 4-6,7-6,6-7 |
| Challenger - Napoli | 2021/10/05 12:55 | Filippo Baldi v Petros Tsitsipas | 6-4,3-6,6-4 |
| Challenger - Napoli | 2021/10/04 08:00 | Bogdan Ionut Apostol v Petros Tsitsipas | 6-3,6-2 |
| Challenger - Sibiu | 2021/09/28 08:40 | Damir Dzumhur v Petros Tsitsipas | 6-2,6-0 |
| Cupa Davis | 2021/09/18 09:00 | Petros Tsitsipas v Ricardas Berankis | 1-6,3-6 |
| Challenger - Cassis | 2021/09/05 12:45 | Ramkumar Ramanathan v Petros Tsitsipas | 6-4,6-4 |
| ITF - M15 Oldenzaal | 2021/08/19 11:20 | Daniel De Jonge v Petros Tsitsipas | 6-2,6-2 |
| ITF - M15 Oldenzaal | 2021/08/18 15:00 | Petros Tsitsipas v Gabriel Alejandro Hidalgo | 7-5,6-2 |
| ITF - M25 Portimao | 2021/11/01 11:25 | Paul Jubb v Sebastian Fanselow | 1-6,7-6,4-6 |
| ITF - M25 Portimao | 2021/10/30 12:00 | Sebastian Fanselow v Maximilian Neuchrist | 6-1,4-6,6-4 |
| ITF - M25 Portimao | 2021/10/29 09:30 | Sebastian Fanselow v Petros Chrysochos | 6-3,6-0 |
| ITF - M25 Portimao | 2021/10/28 09:00 | Sebastian Fanselow v Pablo Llamas Ruiz | 6-4,4-6,6-4 |
| ITF - M25 Portimao | 2021/10/27 09:00 | Sebastian Fanselow v Mehdi Sadaoui | 6-4,6-3 |
| ITF - M25 Quinta do Lago | 2021/10/21 09:00 | Sebastian Fanselow v Maximilian Neuchrist | 3-6,6-4,3-6 |
| ITF - M25 Quinta do Lago | 2021/10/20 08:55 | Sebastian Fanselow v Rio Noguchi | 6-3,7-6 |
| ITF - M25 Loule | 2021/10/13 15:40 | Sebastian Fanselow v Pedro Araujo | 4-6,6-1,0-6 |