Stadium: Central Round: 26 Ground: Hardcourt outdoor
| ITF M15 Torello | 2021/11/03 09:00 | Vilius Gaubas v Noah Lopez | 1-6,7-5,7-6 |
| ITF M15 Madrid | 2021/10/29 07:30 | Vilius Gaubas v Diego A B Sanchez | 1-6,1-6 |
| ITF M15 Madrid | 2021/10/28 09:30 | Vilius Gaubas v Vladislav Ivanov | 6-7,6-1,6-2 |
| ITF M15 Madrid | 2021/10/27 07:55 | Lilian Marmousez v Vilius Gaubas | 6-1,3-6,6-7 |
| Davis Cup | 2021/09/19 08:45 | Alexandros Skorilas v Vilius Gaubas | 6-4,6-4 |
| ITF M15 Parnu | 2021/08/04 10:15 | Mattias Siimar v Vilius Gaubas | 4-6,6-1,7-5 |
| ITF M15 Castelo Branco | 2021/07/27 08:30 | Vilius Gaubas v Gilbert S K Junior | 4-6,3-6 |
| ITF M15 Torello | 2021/11/02 15:35 | Mario Mansilla Diez v Alessandro Ingarao | 6-2,6-3 |
| ITF M15 Madrid | 2021/10/29 07:30 | Mario Mansilla Diez v Coleman Wong | 5-7,1-6 |
| ITF M15 Madrid | 2021/10/28 09:30 | Alejandro Moro Canas v Mario Mansilla Diez | 5-7,6-3,6-7 |
| ITF M15 Madrid | 2021/10/27 10:30 | Mario Mansilla Diez v Max Alcala Gurri | 6-3,6-7,6-1 |
| ITF M15 Girona | 2021/10/21 08:00 | Mario Mansilla Diez v Pol Toledo Bague | 3-6,2-6 |
| ITF M15 Girona | 2021/10/20 11:20 | Maxime Mora v Mario Mansilla Diez | 2-6,7-5,5-7 |
| ITF M15 Girona | 2021/10/19 08:00 | Ignasi De Rueda De Genover v Mario Mansilla Diez | 0-6,4-6 |
| ITF M15 Girona | 2021/10/18 08:00 | Mario Mansilla Diez v Noah Lopez | 6-2,6-0 |