Stadium: Court 3 Round: 25 Ground: Clay
| Challenger - Biella | 2021/05/03 08:30 | Viktor Galovic v Dimitar Kuzmanov | 6-4,6-2 |
| Challenger - Biella | 2021/05/02 12:30 | Stefano Reitano v Dimitar Kuzmanov | 6-2,2-6,2-6 |
| Challenger - Oeiras | 2021/04/07 14:00 | Dimitar Kuzmanov v Ernesto Escobedo | 6-2,6-2 |
| Challenger - Oeiras | 2021/04/05 12:25 | Dimitar Kuzmanov v Lucas Miedler | 6-1,6-0 |
| Challenger - Zadar | 2021/03/28 10:00 | Nikola Milojevic v Dimitar Kuzmanov | 2-6,6-2,7-6 |
| Challenger - Zadar | 2021/03/26 11:40 | Dimitar Kuzmanov v Blaz Kavcic | 6-4,6-1 |
| Challenger - Zadar | 2021/03/25 10:45 | Dimitar Kuzmanov v Zdenek Kolar | 6-4,6-3 |
| Challenger - Zadar | 2021/03/23 12:50 | Gian Marco Moroni v Dimitar Kuzmanov | 4-6,4-6 |
| Challenger - Rom | 2021/04/29 14:40 | Cem Ilkel v Lorenzo Giustino | 6-4,6-2 |
| Challenger - Rom | 2021/04/27 12:25 | Lorenzo Giustino v Juan Pablo Varillas | 6-1,7-5 |
| Challenger - Rom | 2021/04/23 13:05 | Lorenzo Giustino v Vit Kopriva | 6-1,5-7,3-6 |
| Challenger - Rom | 2021/04/22 09:00 | Lorenzo Giustino v Sergiy Stakhovsky | 6-4,6-4 |
| Challenger - Rom | 2021/04/21 09:00 | Lorenzo Giustino v Filip Horansky | 7-6,7-5 |
| Challenger - Split | 2021/04/13 15:20 | Andrea Collarini v Lorenzo Giustino | 6-4,6-4 |
| ATP - Marbella | 2021/04/05 10:00 | Henri Laaksonen v Lorenzo Giustino | 7-5,3-6,6-1 |
| ATP - Marbella | 2021/04/04 10:00 | Roberto Marcora v Lorenzo Giustino | 6-7,4-6 |