Stadium: Court 4 Round: 26 Ground: Hardcourt indoor
| ITF M15 St Petersburg | 2021/04/14 11:55 | Naoki Tajima v Alexander Wolfschmidt | 6-1,6-2 |
| ITF M15 St Petersburg | 2021/04/07 07:00 | Naoki Tajima v Alexey Zakharov | 3-6,6-1,3-6 |
| ITF M15 Monastir | 2021/03/04 11:15 | Naoki Tajima v Franco Agamenone | 0-6,3-6 |
| ITF M15 Monastir | 2021/03/03 13:20 | Stefano Reitano v Naoki Tajima | 1-6,0-6 |
| ITF M15 Monastir | 2021/02/23 08:00 | Alexis Gautier v Naoki Tajima | 7-5,6-4 |
| ITF M15 Monastir | 2021/02/18 11:00 | Naoki Tajima v Jose Fco. Vidal Azorin | 3-6,5-7 |
| ITF M15 Monastir | 2021/02/16 13:00 | Marvin Moeller v Naoki Tajima | 2-6,3-6 |
| ITF M15 Monastir | 2021/02/09 08:30 | Naoki Tajima v Naoki Nakagawa | 5-7,0-6 |
| ITF M15 St Petersburg | 2021/04/14 07:00 | Maxim Ratniuk v Marat Deviatiarov | 7-6,6-7,6-7 |
| ITF M15 Sharm El Sheikh | 2021/03/31 09:50 | Marat Deviatiarov v Alessandro Bega | 0-6,3-6 |
| ITF M15 Sharm El Sheikh | 2021/03/25 07:30 | Marat Deviatiarov v Makoto Ochi | 6-7,3-6 |
| ITF M15 Sharm El Sheikh | 2021/03/24 07:30 | Marat Deviatiarov v Babji Siva Atturu | 6-2,6-0 |
| ITF M15 Sharm El Sheikh | 2021/03/17 07:30 | Marat Deviatiarov v Petros Chrysochos | 3-6,2-6 |
| ITF M15 Kazan | 2021/03/10 11:30 | Alexander Stepin v Marat Deviatiarov | 6-4,7-5 |
| ITF M15 St Petersburg | 2021/02/11 12:55 | Jan Choinski v Marat Deviatiarov | 6-4,6-7,6-1 |
| ITF M15 St Petersburg | 2021/02/10 10:40 | Alibek Kachmazov v Marat Deviatiarov | 2-6,4-6 |