Stadium: M (CC) Round: 62 Ground: Clay
| ITF M15 - Oldenzaal | 2021/08/15 10:15 | Adrian Oetzbach v Mark Simons | 6-1,6-2 |
| ITF M25 - Frankfurt am Main | 2021/08/11 11:15 | Adrian Oetzbach v Taiyo Yamanaka | 5-7,5-7 |
| ITF M25 - Frankfurt am Main | 2021/08/10 08:25 | Lenny Hampel v Adrian Oetzbach | 2-6,6-0,2-10 |
| ITF M25 - Frankfurt am Main | 2021/08/09 09:00 | Adrian Oetzbach v Oscar Moraing | 6-4,3-6,10-6 |
| ITF M15 - Frederiksberg | 2021/08/04 12:05 | Jonathan Mridha v Adrian Oetzbach | 6-2,6-3 |
| ITF M15 - Frederiksberg | 2021/08/02 10:20 | Adrian Oetzbach v Carl Emil Overbeck | 6-3,1-6,10-4 |
| ITF M15 - Vejle | 2021/07/27 12:20 | Adrian Oetzbach v Vasil Kirkov | 7-5,3-6,3-6 |
| ITF M15 - Vejle | 2021/07/26 08:00 | Adrian Oetzbach v Iiro Vasa | 6-3,7-5 |
| ITF M15 - Oldenzaal | 2021/08/15 12:00 | Jing L Weng v Karlo Cubelic | 3-6,1-6 |
| ITF M25 - Frankfurt am Main | 2021/08/10 08:20 | Daniel Cukierman v Karlo Cubelic | 2-6,6-4,10-2 |
| ITF M25 - Frankfurt am Main | 2021/08/09 11:05 | Jan Soeren Hain v Karlo Cubelic | 3-6,2-6 |
| ITF M25 - Marburg | 2021/07/05 13:55 | Dominik Recek v Karlo Cubelic | 6-4,6-2 |
| ITF M15 - Antalya | 2021/06/06 07:30 | Karlo Cubelic v Vitali Shvets | 5-7,6-4,3-10 |
| ITF M15 - Jerusalem | 2021/05/13 07:00 | Karlo Cubelic v Felix Corwin | 2-6,0-6 |
| 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 |