| UTR Pro Tennis Series Florida | 2021/12/15 15:30 | Matthew Segura v Mercer, J | 6-1,6-3 |
| UTR Pro Tennis Series Florida | 2021/12/14 19:30 | Matthew Segura v Alejandro Moreno | 6-3,7-6 |
| UTR Pro Tennis Series Florida | 2021/12/13 16:50 | Steven Forman v Matthew Segura | 6-2,6-0 |
| UTR Pro Tennis Series Miami | 2021/11/07 15:00 | Matthew Segura v Caula, Bruno | 5-7,6-1,1-6 |
| UTR Pro Tennis Series Miami | 2021/11/06 22:36 | Matthew Segura v Henry Lieberman | 6-2,6-5 |
| UTR Pro Tennis Series Miami | 2021/11/06 15:30 | Matthew Segura v Estevez Maximiliano | 2-6,3-6 |
| UTR Pro Tennis Series Miami | 2021/11/04 17:00 | Matthew Segura v Juan David Velasquez | 6-4,5-4 |
| UTR Pro Tennis Series Miami | 2021/11/03 17:00 | Jerry Barton v Matthew Segura | 4-6,3-5 |
| UTR Pro Tennis Series Florida | 2021/12/16 14:00 | Alejandro Moreno v Mitsui, Shunsuke | 2-3 |
| UTR Pro Tennis Series Florida | 2021/12/14 19:00 | Steven Forman v Mitsui, Shunsuke | 6-3,2-6,3-5 |
| UTR Pro Tennis Series Florida | 2021/12/13 17:00 | Mitsui, Shunsuke v Mercer, J | 6-1,6-0 |
| ITF M15 East Lansing | 2021/11/18 18:00 | Sarmiento, Raymond v Mitsui, Shunsuke | 4-6,6-2,7-6 |
| ITF M15 East Lansing | 2021/11/17 17:55 | Peck, Joshua v Mitsui, Shunsuke | 6-0,4-6,5-7 |
| ITF M15 East Lansing | 2021/11/16 15:00 | Mitsui, Shunsuke v Adit Sinha | 6-2,6-4 |
| ITF - M15 Monastir | 2021/05/11 11:30 | Mitsui, Shunsuke v Beale, Jeremy | 6-7,6-4,2-6 |
| ITF - M15 Monastir | 2021/05/02 08:00 | Mitsui, Shunsuke v Yuta Kikuchi | 1-6,2-6 |