Stadium: Court 5 Round: 26 Ground: Hardcourt outdoor
| ITF M15 - Jerusalem | 2021/05/12 12:00 | Roi Ginat v Karlo Cubelic | 1-6,3-6 |
| ITF M15 - Jerusalem | 2021/05/11 06:30 | Karlo Cubelic v Charles Minc | 5-7,6-4,10-5 |
| ITF M15 - Jerusalem | 2021/05/10 07:00 | Karlo Cubelic v Stefan Simeunovic | 6-1,6-1 |
| ITF M15 - Ramat Hasharon | 2021/05/04 07:00 | Karlo Cubelic v Bradley Paliska | 4-6,4-6 |
| ITF M15 - Ramat Hasharon | 2021/05/03 07:00 | Karlo Cubelic v Ofek Amoyal | 6-3,6-3 |
| ITF M25 - Meerbusch | 2021/04/11 13:00 | Tomas Papik v Karlo Cubelic | 3-6,2-6 |
| ITF M15 - Sharm El Sheikh | 2021/04/06 07:30 | Karlo Cubelic v Lukas Pokorny | 6-7,1-6 |
| ITF M15 - Sharm El Sheikh | 2021/04/05 10:00 | Karlo Cubelic v Inaki Cabrera Bello | 4-6,7-5,10-8 |
| ITF M15 - Jerusalem | 2021/05/11 07:40 | Jordan Hasson v Felix Corwin | 6-1,1-6,2-6 |
| ITF M15 - Ramat Hasharon | 2021/05/08 07:00 | Felix Corwin v Yshai Oliel | 1-6,4-6 |
| ITF M15 - Ramat Hasharon | 2021/05/07 07:00 | Marat Deviatiarov v Felix Corwin | 5-7,4-6 |
| ITF M15 - Ramat Hasharon | 2021/05/06 08:30 | Filip Bergevi v Felix Corwin | 2-6,2-6 |
| ITF M15 - Ramat Hasharon | 2021/05/05 07:30 | Dylan Salton v Felix Corwin | 0-6,5-7 |
| Challenger Salinas | 2021/04/18 15:00 | Gonzalo Villanueva v Felix Corwin | 6-7,6-4,7-5 |
| UTR Pro Tennis Series - Cancún | 2021/04/04 13:00 | Felix Corwin v Wilson Leite | 6-3,4-6,6-3 |
| UTR Pro Tennis Series - Cancún | 2021/04/03 13:00 | Felix Corwin v Gabriel Evans | 6-3,5-2 |