Stadium: Court 1 Round: 26 Ground: Clay
| Challenger Praga | 2021/05/04 14:15 | Dmitry Popko v Sergiy Stakhovsky | 3-6,4-6 |
| Challenger Praga | 2021/05/03 11:30 | Denis Istomin v Sergiy Stakhovsky | 6-7,1-6 |
| Challenger Praga | 2021/05/02 14:40 | Vojtech Petr v Sergiy Stakhovsky | 3-6,7-6,5-7 |
| Challenger Ostrava | 2021/04/28 09:00 | Elias Ymer v Sergiy Stakhovsky | 6-1,6-2 |
| Challenger Ostrava | 2021/04/27 09:10 | Patrik Rikl v Sergiy Stakhovsky | 4-6,2-6 |
| Challenger Rzym | 2021/04/22 09:00 | Lorenzo Giustino v Sergiy Stakhovsky | 6-4,6-4 |
| Challenger Rzym | 2021/04/20 11:40 | Sergiy Stakhovsky v Mathias Bourgue | 6-4,3-6,7-5 |
| Challenger Lugano | 2021/03/25 11:00 | Sergiy Stakhovsky v Vitaliy Sachko | 3-6,1-6 |
| Challenger Praga | 2021/05/04 10:25 | Zdenek Kolar v Sumit Nagal | 2-6,4-6 |
| ATP Monachium | 2021/04/24 12:15 | Norbert Gombos v Sumit Nagal | 6-4,6-7,6-1 |
| ATP Barcelona | 2021/04/19 11:25 | Sumit Nagal v Pierre-Hugues Herbert | 5-7,0-6 |
| ATP Barcelona | 2021/04/18 10:25 | Thomas Fabbiano v Sumit Nagal | 6-7,3-6 |
| ATP Barcelona | 2021/04/17 13:25 | Illya Marchenko v Sumit Nagal | 6-3,2-6,5-7 |
| ATP Monte Carlo | 2021/04/10 11:00 | Stefano Travaglia v Sumit Nagal | 6-3,6-0 |
| ATP Cagliari | 2021/04/06 12:55 | Sumit Nagal v Jozef Kovalik | 6-3,1-6,3-6 |
| ATP Cagliari | 2021/04/05 09:00 | Sumit Nagal v Maxime Janvier | 6-2,6-1 |