Stadium: Court 8 Round: 54 Ground: Hardcourt outdoor
| ITF M15 Antalya | 2021/06/27 06:30 | Inigo G Olasagasti v Petr Bar Biryukov | 7-6,1-6,10-5 |
| ITF M15 Shymkent | 2021/06/02 11:45 | Petr Bar Biryukov v Yan Bondarevskiy | 3-6,2-6 |
| ITF M15 Shymkent | 2021/06/01 09:20 | Antonio Campo v Petr Bar Biryukov | 4-6,6-3,10-7 |
| ITF M15 Shymkent | 2021/05/31 06:35 | Alexey Dubinin v Petr Bar Biryukov | 2-6,2-6 |
| ITF M15 Shymkent | 2021/05/24 04:00 | Louroi Martinez v Petr Bar Biryukov | 6-4,6-1 |
| ITF M15 St Petersburg | 2021/04/15 09:00 | Evgeny Tyurnev v Petr Bar Biryukov | 6-1,6-1 |
| ITF M15 St Petersburg | 2021/04/13 09:00 | Petr Bar Biryukov v Kirill Saplin | 6-4,6-1 |
| ITF M15 St Petersburg | 2021/04/06 09:00 | Ivan Nedelko v Petr Bar Biryukov | 6-3,6-1 |
| ITF M25 Nur-Sultan | 2021/07/05 04:00 | Grigory Kuklin v Danil Ozernoy | 5-7,2-6 |
| Challenger Almaty Qual | 2021/06/13 08:00 | Filip Cristian Jianu v Danil Ozernoy | 6-2,6-1 |
| ITF M15 Shymkent | 2021/06/02 10:10 | Danil Ozernoy v Alexander Shevchenko | 2-6,2-6 |
| ITF M15 Shymkent | 2021/05/26 04:00 | Pavel Verbin v Danil Ozernoy | 7-6,4-6,7-5 |
| ITF M15 Shymkent | 2021/04/12 06:40 | Piotr Pawlak v Danil Ozernoy | 6-1,7-6 |
| ITF M15 Shymkent | 2021/04/07 07:25 | Bulat Galiev v Danil Ozernoy | 6-4,6-1 |
| ITF M15 Shymkent | 2021/04/06 07:40 | Kirill Kolganov v Danil Ozernoy | 6-7,2-6 |
| ITF M15 Shymkent | 2021/04/05 07:00 | Alexander Chernomaz v Danil Ozernoy | 4-6,4-6 |