Stadium: Court 1 Round: 44 Ground: Hardcourt outdoor
| ITF M25 Sintra | 2021/09/05 08:30 | Alan F R Fierros v Luigi Castelletti | 6-2,6-0 |
| ITF M15 Perugia | 2021/07/18 09:00 | Wishaya Trongcharoenchaikul v Luigi Castelletti | 6-4,6-3 |
| ITF M15 L'Aquila | 2021/07/12 10:30 | Luigi Castelletti v Alessandro Procopio | 6-1,2-6,8-10 |
| ITF M15 L'Aquila | 2021/07/11 11:00 | Pedro Ortega v Luigi Castelletti | 3-6,3-6 |
| ITF M15 Almada | 2021/07/07 12:15 | Egor Noskin v Luigi Castelletti | 6-7,7-5,6-1 |
| ITF M15 Almada | 2021/07/05 10:00 | Harry Wendelken v Luigi Castelletti | 6-0,6-0 |
| ITF M15 Gaiba | 2021/06/09 12:50 | Benjamin Lock v Luigi Castelletti | 6-1,6-3 |
| ITF M15 Bucharest | 2021/05/23 15:00 | Simon Beaupain v Luigi Castelletti | 6-1,6-2 |
| UTR Pro Tennis Series Sofia | 2021/09/04 07:30 | Alexander Lazov v George Lazarov | 3-5 |
| UTR Pro Tennis Series Sofia | 2021/09/03 07:00 | George Lazarov v Christos Keisidis | 6-4,6-4 |
| UTR Pro Tennis Series Sofia | 2021/09/02 07:00 | Ivan Mikhaylyuk v George Lazarov | 3-6,1-6 |
| UTR Pro Tennis Series Sofia | 2021/09/01 06:30 | Volodymyr Uzhylovskyi v George Lazarov | 1-6,6-1,1-5 |
| UTR Pro Tennis Series Sofia | 2021/08/31 09:30 | Valentin Vanta v George Lazarov | 6-4,6-0 |
| UTR Pro Tennis Series Sofia | 2021/08/30 12:00 | Warren Sinius v George Lazarov | 2-6,2-5 |
| UTR Pro Tennis Series Sofia | 2021/08/29 12:00 | George Lazarov v Mario Radev | 6-0,6-1 |