Stadium: Court 10 Round: 62 Ground: Clay
| ITF - M15 Sofia | 2021/07/07 07:00 | Denis Klok v Aleksandr Braynin | 4-6,3-6 |
| ITF - M25 Belgrad | 2021/06/27 07:00 | Denis Klok v George Botezan | 3-6,1-6 |
| ITF - M15 Antalya | 2021/04/28 11:40 | Francesco Maestrelli v Denis Klok | 1-6,6-2,6-1 |
| ITF - M15 Antalya | 2021/04/27 07:00 | Denis Klok v Vladimir Korolev | 6-1,4-6,10-3 |
| ITF - M15 Antalya | 2021/04/26 07:00 | Denis Klok v Vojtech Mares | 6-3,6-2 |
| ITF - M15 Antalya | 2021/04/25 07:00 | Denis Klok v Vladislav Ivanov | 6-1,7-6 |
| ITF - M15 Antalya | 2021/04/18 07:00 | Denis Klok v Noel Larwig | 5-7,0-6 |
| ITF - M15 Shymkent | 2021/04/15 04:00 | Denis Klok v Ivan Gakhov | 5-7,6-7 |
| ITF - M25 Vic | 2021/05/16 08:00 | Hans Albert Schubert v Abedallah Shelbayh | 1-6,5-7 |
| ITF - M15 Sharm El Sheikh | 2021/04/04 12:30 | Daniel Cox v Hans Albert Schubert | 6-1,6-2 |
| ITF - M15 Sharm El Sheikh | 2021/03/28 09:30 | Hans Albert Schubert v Yaron Guberman | 1-6,5-7 |
| ITF - M15 Torello | 2020/12/06 10:00 | Hans Albert Schubert v Luigi Castelletti | 4-6,3-6 |
| ITF - M15 Cairo | 2020/11/22 12:00 | Adham Gaber v Hans Albert Schubert | 6-1,7-5 |
| ITF - M15 Sharm El Sheikh | 2020/11/16 12:00 | Hans Albert Schubert v Leonid Sheyngezikht | 0-6,3-6 |
| ITF - M15 Sharm El Sheikh | 2020/11/08 10:00 | Volodymyr Uzhylovskyi v Hans Albert Schubert | 6-3,6-1 |
| ITF - M15 Santo Domingo | 2019/12/11 16:40 | Hans Albert Schubert v Arklon H D Pino | 1-6,1-6 |