Stadium: Court 1 Round: 25 Ground: Clay
| Challenger Biella | 2021/05/04 08:00 | Alessandro Giannessi v Juan Pablo Varillas | 4-6,5-7 |
| Challenger Rome | 2021/05/01 12:45 | Alessandro Giannessi v Juan Manuel Cerundolo | 6-4,4-6,5-7 |
| Challenger Rome | 2021/04/30 11:20 | Alessandro Giannessi v Thanasi Kokkinakis | 7-5,3-6,7-5 |
| Challenger Rome | 2021/04/28 11:20 | Alessandro Giannessi v Jay Clarke | 6-2,6-4 |
| Challenger Rome | 2021/04/26 11:05 | Alessandro Giannessi v Guido Andreozzi | 6-3,6-3 |
| Challenger Belgrade | 2021/04/12 11:20 | Alessandro Giannessi v Maxime Janvier | 3-6,6-4,6-4 |
| Challenger Belgrade | 2021/04/11 13:05 | Alessandro Giannessi v Marko Topo | 2-6,7-6,6-2 |
| Challenger Marbella | 2021/04/03 10:00 | Alessandro Giannessi v Gianluca Mager | 7-6,4-6,1-6 |
| ATP Munich | 2021/04/24 12:15 | Prajnesh Gunneswaran v Dennis Novak | 4-6,6-3,5-7 |
| Challenger Tallahassee | 2021/04/19 17:00 | Prajnesh Gunneswaran v Pedro Sakamoto | 2-6,6-2,4-6 |
| Challenger Orlando | 2021/04/15 16:30 | Prajnesh Gunneswaran v Jack Sock | 3-6,4-6 |
| Challenger Orlando | 2021/04/13 16:20 | Prajnesh Gunneswaran v Matthew Ebden | 6-4,6-1 |
| ATP Dubai | 2021/03/13 07:00 | Yuki Bhambri v Prajnesh Gunneswaran | 6-1,6-4 |
| Challenger Nur-Sultan | 2021/03/06 06:35 | Tomas Machac v Prajnesh Gunneswaran | 6-3,1-6,6-2 |
| Challenger Nur-Sultan | 2021/03/05 05:00 | James Duckworth v Prajnesh Gunneswaran | 4-6,6-2,6-7 |
| Challenger Nur-Sultan | 2021/03/02 04:00 | Julian Lenz v Prajnesh Gunneswaran | 6-3,2-6,3-6 |