| ITF M15 Waco | 07/06 14:25 | 25 | Grassi Mazzuchi, Juan Pablo v Colin Markes | 5-7,3-6 | |
| ITF M25 Austin | 11/18 17:00 | 26 | Eliot Spizzirri v Grassi Mazzuchi, Juan Pablo | 7-6,7-5 | |
| ITF M25 Austin | 11/17 20:50 | 25 | Grassi Mazzuchi, Juan Pablo v Woldeab, Siem | 7-6,6-2 | |
| ITF M25 Austin | 11/16 18:55 | 54 | Grassi Mazzuchi, Juan Pablo v Ethan Quinn | 7-6,6-7,10-7 | |
| ITF M25 Austin | 11/15 17:00 | 54 | Grassi Mazzuchi, Juan Pablo v Bucan, Aleksa | 3-6,6-1,10-5 | |
| ITF M15 Fayetteville | 11/03 14:30 | 25 | Grassi Mazzuchi, Juan Pablo v Alexandre Reco | 4-6,4-6 | |
| Fayetteville, AR, Singles Qualifying, M-ITF-USA-31 | 11/02 14:00 | 54 | van Emburgh, Jake v Grassi Mazzuchi, Juan Pablo | Retired | |
| UTR Pro Tennis Series Texas | 09/26 13:00 | - | Grassi Mazzuchi, Juan Pablo v Rollins, Pierce | 6-3,5-4 | |
| UTR Pro Tennis Series Texas | 09/25 17:30 | - | Grassi Mazzuchi, Juan Pablo v Perego, Giulio | 6-1,5-2 | |
| UTR Pro Tennis Series Texas | 09/24 16:00 | - | Grassi Mazzuchi, Juan Pablo v George Goldhoff | 6-0,6-3 | |
| UTR Pro Tennis Series Texas | 09/22 13:00 | - | Grassi Mazzuchi, Juan Pablo v Perot, Raphael | 6-2,5-2 | |
| UTR Pro Tennis Series Texas | 09/21 14:30 | - | Grassi Mazzuchi, Juan Pablo v Lah, Sven | 6-3,4-6,5-4 | |
| UTR Pro Tennis Series Texas | 09/20 13:00 | - | Abbrat, Austin v Grassi Mazzuchi, Juan Pablo | 4-6,5-6 | |
| UTR Pro Tennis Series Florida | 06/01 13:00 | - | Jonah Braswell v Grassi Mazzuchi, Juan Pablo | 7-6,6-4 | |
| UTR Pro Tennis Series Florida | 05/31 19:30 | - | Grassi Mazzuchi, Juan Pablo v Finn Bass | 6-7,3-6 | |
| ITF M15 Cancun | 08/21 19:25 | 25 | Thiago Agustin Tirante v Grassi Mazzuchi, Juan Pablo | 6-4,6-2 | |
| ITF M15 Cancun | 08/19 20:00 | 54 | Grassi Mazzuchi, Juan Pablo v Carnevale-Miino, Tommaso | 7-6,6-3 | |
| ITF M15 Cancun | 08/19 14:30 | 54 | Grassi Mazzuchi, Juan Pablo v Jirasook, Kyler | 6-2,6-2 | |
| ITF M15 Cancun | 08/14 14:00 | 25 | Matija Pecotic v Grassi Mazzuchi, Juan Pablo | 6-1,6-3 | |
| Buenos Aires, Singles Qualifying M-ITF-ARG-22A | 07/11 16:20 | 26 | Camilo Ugo Carabelli v Grassi Mazzuchi, Juan Pablo | 4-6,6-4,6-3 | |
| Buenos Aires, Singles Qualifying M-ITF-ARG-22A | 07/10 12:00 | 25 | Franco Roncadelli v Grassi Mazzuchi, Juan Pablo | 3-6,6-7 | |
| Buenos Aires, Singles M-ITF-ARG-06B | 07/02 17:45 | 25 | Grassi Mazzuchi, Juan Pablo v Oscar Jose Gutierrez | 6-4,1-6,4-6 | |
| ITF M15 Cancun | 06/04 15:25 | 25 | Grassi Mazzuchi, Juan Pablo v El Midhawy, Adam | 1-6,1-6 | |
| ITF M15 Cancun | 05/31 14:00 | 27 | Grassi Mazzuchi, Juan Pablo v Gomez, Alejandro | 3-6,2-6 | |
| ITF M15 Cancun | 05/30 15:45 | 26 | Lopez Villasenor, Gerardo v Grassi Mazzuchi, Juan Pablo | 4-6,6-0,4-6 | |
| ITF M15 Cancun | 05/29 13:30 | 25 | Shamma, Nicholas v Grassi Mazzuchi, Juan Pablo | 1-6,1-6 | |
| ITF M15 Cancun | 05/27 18:00 | 54 | Grassi Mazzuchi, Juan Pablo v Rowland Phillips | 6-2,6-1 | |
| ITF M15 Cancun | 05/27 15:30 | 54 | Grassi Mazzuchi, Juan Pablo v Mayagoitia, Ricardo David | Retired | |
| ITF M15 Cancun | 05/21 16:00 | 25 | Alexis Canter v Grassi Mazzuchi, Juan Pablo | 2-6,6-3,6-4 | |
| ITF M15 Cancun | 05/13 17:30 | 54 | Grassi Mazzuchi, Juan Pablo v Endara, Ivan | 4-6,4-6 |