Stadium: Court 5 Round: 54 Ground: Hardcourt indoor
| ITF M15 Ithaca | 2021/10/04 13:00 | Maier, Jonas v Bernardi, Mattia | 6-2,6-2 |
| ITF M15 Cancun | 2021/09/26 17:00 | Alex Jones v Maier, Jonas | 6-1,6-2 |
| ITF M15 Cancun | 2021/09/23 19:15 | Maier, Jonas v Osgar O'Hoisin | 6-3,4-6,4-6 |
| ITF M15 Cancun | 2021/09/22 18:10 | Wishaya Trongcharoenchaikul v Maier, Jonas | 1-6,3-6 |
| ITF M15 Cancun | 2021/09/21 14:00 | Maier, Jonas v Samuel Sanchez | 6-3,6-1 |
| UTR Pro Tennis Series California | 2021/08/25 21:30 | Maier, Jonas v Gianluca Brunkow | 5-7,2-6 |
| UTR Pro Tennis Series California | 2021/08/24 21:00 | Maier, Jonas v Gomez, Lucas | 2-6,3-6 |
| UTR Pro Tennis Series California | 2021/08/23 15:00 | Sah, Timothy v Maier, Jonas | 4-6,6-1,6-3 |
| UTR Pro Tennis Series Dallas | 2021/08/08 15:30 | Evan Zhu v Mostardi, Nico | 6-4,5-0 |
| UTR Pro Tennis Series Dallas | 2021/08/07 13:00 | Demulling, Wyatt v Mostardi, Nico | 5-7,5-6 |
| UTR Pro Tennis Series Dallas | 2021/08/05 14:30 | Mostardi, Nico v Acevedo, Nicolas | 2-6,2-6 |
| UTR Pro Tennis Series Dallas | 2021/08/04 14:30 | Mostardi, Nico v Top Nidunjianzan | 7-6,3-6,6-1 |
| UTR Pro Tennis Series Dallas | 2021/08/03 14:30 | Mostardi, Nico v Latinovic, Stefan | 6-2,3-6,1-6 |
| UTR Pro Tennis Series Dallas | 2021/08/02 15:00 | Mostardi, Nico v Kyle Frankel | 4-6,4-5 |
| UTR Pro Tennis Series Atlanta | 2021/07/07 15:30 | Mostardi, Nico v Conner Huertas Del Pino | 6-4,3-6,0-5 |
| UTR Pro Tennis Series Atlanta | 2021/07/06 12:00 | Mostardi, Nico v Nicholas McKinney | 1-6,6-3,3-6 |