Stadium: Court 15 Round: 25 Ground: Hardcourt outdoor
| ITF M25 Tulsa | 2021/06/19 14:00 | Genaro Alberto Olivieri v Sam Riffice | 7-6,7-6 |
| ITF M25 Tulsa | 2021/06/18 14:00 | Gage Brymer v Sam Riffice | 0-6,6-7 |
| ITF M25 Tulsa | 2021/06/17 14:00 | Sam Riffice v Jason Kubler | 6-1,6-4 |
| ITF M25 Tulsa | 2021/06/16 14:00 | Nathan Ponwith v Sam Riffice | 5-7,4-6 |
| Challenger Orlando | 2021/06/12 17:45 | Sam Riffice v Christopher Eubanks | 3-6,6-7 |
| Challenger Orlando | 2021/06/11 17:20 | Ulises Blanch v Sam Riffice | 1-6,5-7 |
| Challenger Orlando | 2021/06/09 14:00 | Roberto Cid Subervi v Sam Riffice | 2-6,2-6 |
| Challenger Orlando | 2021/06/07 15:55 | Sam Riffice v Paolo Lorenzi | 6-2,6-4 |
| Challenger Porto | 2021/07/02 10:00 | Altug Celikbilek v Tatsuma Ito | 7-5,6-3 |
| Challenger Porto | 2021/06/29 10:00 | Tatsuma Ito v Luis Faria | 6-0,6-2 |
| Wimbledon | 2021/06/23 13:45 | Tatsuma Ito v Jason Jung | 2-6,1-6 |
| Wimbledon | 2021/06/22 11:35 | Elias Ymer v Tatsuma Ito | 3-6,4-6 |
| ATP Halle | 2021/06/12 09:00 | Ilya Ivashka v Tatsuma Ito | 6-1,6-3 |
| French Open | 2021/05/24 20:30 | Tatsuma Ito v Altug Celikbilek | 3-6,6-4,5-7 |
| Challenger Zagreb | 2021/05/10 10:25 | Ernests Gulbis v Tatsuma Ito | 7-6,1-6,6-4 |
| Challenger Zagreb | 2021/05/09 13:50 | Akira Santillan v Tatsuma Ito | 4-6,3-6 |