| ITF M15 Novi Sad | 2021/08/03 12:40 | Pedro Boscardin Dias v Duje Kekez | 7-6,6-3 |
| ITF M15 Novi Sad | 2021/07/29 12:40 | Duje Kekez v Filip Misolic | 4-6,0-6 |
| ITF M15 Novi Sad | 2021/07/28 07:25 | Wilson Leite v Duje Kekez | 2-6,3-6 |
| ITF M15 Doboj | 2021/07/15 10:40 | Andrej Nedic v Duje Kekez | 0-6,2-6 |
| ITF M15 Doboj | 2021/07/14 08:30 | Duje Kekez v Aldin Setkic | 7-5,7-6 |
| ITF M25 Velenje | 2021/07/07 08:00 | Toby Alex Kodat v Duje Kekez | 3-6,6-1,7-5 |
| ITF M15 Sarajevo | 2021/06/03 09:00 | Skander Mansouri v Duje Kekez | 7-5,6-4 |
| ITF M15 Sarajevo | 2021/06/02 09:00 | Duje Kekez v Sebastian Prechtel | 6-1,6-1 |
| ITF M15 Heraklion | 2021/06/09 08:00 | Antonio Cayetano March v Christos Keisidis | 4-6,7-6,6-2 |
| ITF M15 Heraklion | 2021/06/08 06:30 | Sean Hodkin v Christos Keisidis | 6-4,5-7,4-10 |
| ITF M15 Heraklion | 2021/06/07 09:00 | Christos Keisidis v Alexander Gaponenko | 6-4,6-1 |
| ITF M15 Heraklion | 2021/06/06 11:00 | Michel-Alexandre Fortin v Christos Keisidis | 0-6,0-6 |
| ITF M15 Heraklion | 2021/05/31 06:30 | Mattia Bellucci v Christos Keisidis | 6-4,6-3 |
| ITF M15 Heraklion | 2021/05/24 06:30 | Christos Keisidis v William Griffith | 2-6,3-6 |
| ITF M15 Heraklion | 2021/05/23 08:00 | Matic Dimic v Christos Keisidis | 2-6,4-6 |
| ITF M15 Heraklion | 2021/05/19 06:30 | Christos Keisidis v Aristotelis Thanos | 2-6,2-6 |