Stadium: Court 3 Round: 25 Ground: Clay
| UTR Pro Tennis Series Barcelona | 2021/08/15 08:00 | Andrey Chepelev v Deviatiarov, Marat | 6-1,6-7,2-6 |
| UTR Pro Tennis Series Barcelona | 2021/08/14 08:00 | Fermin Tenti v Deviatiarov, Marat | 0-6,1-6 |
| UTR Pro Tennis Series Barcelona | 2021/08/12 10:00 | Pujol Navarro, Bruno v Deviatiarov, Marat | 4-6,6-4,5-6 |
| UTR Pro Tennis Series Barcelona | 2021/08/10 08:30 | Luc Fomba v Deviatiarov, Marat | 5-7,3-6 |
| UTR Pro Tennis Series Barcelona | 2021/08/09 11:00 | Deviatiarov, Marat v Federico Zeballos | 5-7,1-6 |
| UTR Pro Tennis Series Barcelona | 2021/08/07 11:00 | Kolisnyk, Olexiy v Deviatiarov, Marat | 6-4,7-5 |
| UTR Pro Tennis Series Barcelona | 2021/08/06 11:30 | Deviatiarov, Marat v Guerrero Melgar, Angel | 6-2,6-1 |
| UTR Pro Tennis Series Barcelona | 2021/08/05 10:00 | Deviatiarov, Marat v Carretero, Pablo | 6-0,6-1 |
| ITF - M15 Monastir | 2021/06/28 08:00 | Saito, Takashi v de Pellegrin, Valentino | 6-3,2-6,10-12 |
| ITF - M15 Monastir | 2021/06/21 12:30 | Saito, Takashi v van Emburgh, Jake | 6-2,3-6,8-10 |
| ITF - M15 Monastir | 2021/06/21 08:00 | Saito, Takashi v Rihane, Youcef | 5-7,6-4,10-3 |
| ITF - M15 Monastir | 2021/06/20 08:00 | Saito, Takashi v Berk Ilkel | 6-2,6-3 |
| ITF - M15 Monastir | 2021/05/06 08:25 | Saito, Takashi v Alexander Donski | 6-7,1-6 |
| ITF - M15 Monastir | 2021/05/05 08:25 | Guido Ivan Justo v Saito, Takashi | 1-6,1-6 |
| ITF - M15 Monastir | 2021/05/04 08:00 | Saito, Takashi v Marcello Serafini | 7-5,2-6,10-8 |
| ITF - M15 Monastir | 2021/05/03 12:00 | Saito, Takashi v Francesco Cano | 6-0,6-3 |