Stadium: Court 4 Round: 26 Ground: Clay
| ITF M25 Muttenz | 2021/08/18 12:50 | Gabriele Moghini v Luca Castelnuovo | 6-7,1-6 |
| Challenger Tampere | 2021/07/18 10:20 | Kyrian Jacquet v Luca Castelnuovo | 6-7,6-1,6-0 |
| Challenger Amersfoort | 2021/07/11 14:25 | Michael Geerts v Luca Castelnuovo | 7-6,6-2 |
| ITF M15 Poprad | 2021/07/08 08:00 | Luca Castelnuovo v Roman Andres Burruchaga | 2-6,3-6 |
| ITF M15 Poprad | 2021/07/07 10:10 | Luca Castelnuovo v Jan Jermar | 7-6,6-2 |
| ITF M25 Wroclaw | 2021/06/27 15:30 | Luca Castelnuovo v Piotr Grynkowski | 6-4,6-7,7-10 |
| ITF M25 Klosters | 2021/06/23 10:30 | Luca Castelnuovo v Tim Handel | 6-7,2-6 |
| ITF M25 Klosters | 2021/06/21 07:00 | Luca Castelnuovo v Leopold Zima | 6-2,3-6,10-6 |
| ITF M25 Muttenz | 2021/08/17 14:10 | Mateus Alves v Oscar Jose Gutierrez | 3-6,6-2,1-6 |
| Challenger San Marino | 2021/08/08 12:50 | Orlando Luz v Oscar Jose Gutierrez | 7-5,6-3 |
| ITF M25 Bolzano | 2021/08/03 18:35 | Arthur Reymond v Oscar Jose Gutierrez | 6-4,3-6,6-2 |
| Challenger Tampere | 2021/07/19 09:00 | Geoffrey Blancaneaux v Oscar Jose Gutierrez | 6-4,6-2 |
| Challenger Tampere | 2021/07/18 08:00 | Roni Rikkonen v Oscar Jose Gutierrez | 2-6,5-7 |
| ATP Bastad | 2021/07/11 09:00 | Arthur Rinderknech v Oscar Jose Gutierrez | 6-4,7-5 |
| ITF M25 Velenje | 2021/07/08 09:45 | Oscar Jose Gutierrez v Peter Goldsteiner | 6-7,6-3,4-6 |
| ITF M25 Velenje | 2021/07/07 08:00 | Oscar Jose Gutierrez v Constantin Bittoun Kouzmine | 4-6,6-3,6-4 |