Stadium: Court 5 Round: 62 Ground: Clay
| ITF M25 Wroclaw | 2021/06/27 14:00 | Daniel Dutra Da Silva v Michal Wozniak | 6-3,6-2 |
| ITF M15 Antalya | 2021/06/23 12:20 | Daniel Dutra Da Silva v Alex Barrena | 4-6,1-6 |
| ITF M15 Antalya | 2021/06/10 07:00 | Timo Stodder v Daniel Dutra Da Silva | 1-6,7-5,6-1 |
| ITF M15 Novomoskovsk | 2021/06/03 10:00 | Viacheslav Bielinskyi v Daniel Dutra Da Silva | 6-4,1-6,14-12 |
| ITF M15 Novomoskovsk | 2021/05/26 06:15 | Daniel Dutra Da Silva v Alex M Pujolras | 7-6,6-1 |
| ITF M25 Pensacola | 2021/05/19 20:15 | Patrick Kypson v Daniel Dutra Da Silva | 5-7,7-5,6-3 |
| ITF M25 Naples | 2021/02/24 14:55 | Alexander Ritschard v Daniel Dutra Da Silva | 6-3,6-3 |
| ITF M25 Naples | 2021/02/23 16:50 | Daniel Dutra Da Silva v Dragos Constantin Ignat | 6-3,6-4 |
| ITF M15 Skopje | 2021/06/07 08:30 | Leonid Sheyngezikht v Ondrej Horak | 6-0,7-5 |
| ITF M15 Skopje | 2021/06/06 09:00 | Ondrej Horak v Luigi Sorrentino | 6-0,1-6,11-9 |
| ITF M15 Skopje | 2021/05/30 09:30 | Ondrej Horak v Viktor Jovic | 4-6,3-6 |
| ITF M25 Most | 2021/05/23 14:00 | Martin Damm v Ondrej Horak | 7-5,6-4 |
| ITF M25 Jablonec Nad Nisou | 2021/05/17 07:30 | Ondrej Horak v Tomas Papik | 1-6,4-6 |
| ITF M25 Jablonec Nad Nisou | 2021/05/16 08:30 | George Loffhagen v Ondrej Horak | 5-7,1-6 |
| ITF M25 Prague | 2021/05/10 08:00 | Jan Satral v Ondrej Horak | 6-1,6-2 |
| ITF M25 Prague | 2021/05/09 10:00 | Ondrej Horak v Jan Jermar | 7-6,6-3 |