Stadium: Court Tsitsipas Round: 25 Ground: Hardcourt outdoor
| ITF M15 Monastir | 2021/05/06 10:05 | Mohamed Aziz Dougaz v Karlis Ozolins | 6-4,6-3 |
| ITF M15 Monastir | 2021/05/04 10:30 | Jabari Stafford v Karlis Ozolins | 1-6,1-6 |
| ITF M15 Monastir | 2021/04/27 08:30 | Karlis Ozolins v Oscar Jose Gutierrez | 4-6,2-6 |
| ITF M15 Monastir | 2021/04/20 09:00 | Karlis Ozolins v Viktor Jovic | 7-5,4-6,3-6 |
| ITF M15 Sharm El Sheikh | 2021/03/17 07:30 | Karlis Ozolins v Illya Beloborodko | 2-6,1-6 |
| ITF M15 Sharm El Sheikh | 2021/03/10 10:55 | Karlis Ozolins v Jacopo Berrettini | 1-6,4-6 |
| ITF M15 St Petersburg | 2021/02/09 11:15 | Karlis Ozolins v Konstantin Kravchuk | 4-6,3-6 |
| ITF M15 St Petersburg | 2021/02/04 07:00 | Alexey Zakharov v Karlis Ozolins | 4-6,6-2,7-6 |
| ITF M15 Heraklion | 2021/06/10 07:30 | Alexis Musialek v Aristotelis Thanos | 6-4,6-1 |
| ITF M15 Heraklion | 2021/06/09 09:55 | Aristotelis Thanos v Kelsey Stevenson | 6-2,7-5 |
| ITF M15 Heraklion | 2021/06/01 08:00 | Aristotelis Thanos v Martin Breysach | 3-6,3-6 |
| ITF M15 Heraklion | 2021/05/25 06:30 | Aristotelis Thanos v Lorenzo Joaquin Rodriguez | 6-2,6-0 |
| ITF M15 Heraklion | 2021/05/23 10:00 | Aristotelis Thanos v Stephanos Schinas | 5-7,6-1,10-7 |
| ITF M15 Heraklion | 2021/05/20 06:30 | Yuta Shimizu v Aristotelis Thanos | 3-6,6-1,7-6 |
| ITF M15 Heraklion | 2021/05/19 06:30 | Christos Keisidis v Aristotelis Thanos | 2-6,2-6 |
| ITF M15 Heraklion | 2021/05/18 06:30 | Aristotelis Thanos v Eric Morris | 7-6,6-0 |