Stadium: Court 2 Round: 25 Ground: Clay
| ITF M15 Sibenik | 2021/04/20 08:00 | Domagoj Biljesko v Christian Sigsgaard | 6-1,6-7,4-10 |
| ITF M15 Sibenik | 2021/04/19 09:15 | Domagoj Biljesko v Luka Mikrut | 6-4,7-5 |
| ITF M15 Sibenik | 2021/04/18 10:00 | Domagoj Biljesko v Peter Samosi | 6-2,6-2 |
| ITF M15 Opatija | 2021/03/23 09:00 | Matic Spec v Domagoj Biljesko | 7-5,6-2 |
| ITF M15 Opatija | 2021/03/22 11:45 | Tadija Radovanovic v Domagoj Biljesko | 6-7,1-6 |
| ITF M15 Rovinj | 2021/03/15 08:30 | Domagoj Biljesko v Victor Vlad Cornea | 3-6,7-5,5-10 |
| ITF M15 Porec | 2021/03/08 14:00 | Mauro De Maio v Domagoj Biljesko | 6-3,7-6 |
| ITF M15 Porec | 2021/03/07 14:30 | Luka Petrovic v Domagoj Biljesko | 5-7,6-3,8-10 |
| ITF M15 Prijedor | 2021/05/13 07:00 | Alen Rogic-Hadzalic v Maikel De Boes | 6-4,6-7,6-3 |
| ITF M15 Cairo | 2021/04/25 11:00 | Maikel De Boes v Alessandro Ragazzi | 7-5,1-6,7-10 |
| ITF M15 Cairo | 2021/04/18 08:30 | Maikel De Boes v Juan Ignacio Alcalde | 5-7,3-6 |
| ITF M15 Cairo | 2021/04/13 12:30 | Yanais Laurent v Maikel De Boes | 6-2,3-6,10-8 |
| ITF M15 Cairo | 2021/04/12 08:30 | Maikel De Boes v Volodymyr Uzhylovskyi | 7-6,6-3 |
| ITF M15 Monastir | 2021/03/28 08:00 | Igor Marcondes v Maikel De Boes | 6-1,6-1 |
| ITF M15 Monastir | 2021/03/22 08:00 | Maikel De Boes v Aliaksandr Liaonenka | 5-7,2-6 |
| ITF M15 Monastir | 2021/03/21 13:00 | Naman Sharma v Maikel De Boes | 3-6,2-6 |