Stadium: CC Round: 54 Ground: Clay
| Challenger Luedenscheid | 2023/07/30 10:35 | Karlo Cubelic v Marvin Moeller | 3-6,6-3,2-6 |
| ITF M15 Metzingen | 2023/07/24 12:00 | Karlo Cubelic v Rostislav Galfinger | 2-6,4-6 |
| ITF M15 Metzingen | 2023/07/23 07:30 | Karlo Cubelic v Stefan Peter Hampe | 6-3,2-6,10-5 |
| ITF M15 Uslar | 2023/07/17 08:00 | Karlo Cubelic v Aaron James Williams | 6-7,6-4,6-10 |
| ITF M25 Kassel | 2023/07/12 11:55 | Hady Habib v Karlo Cubelic | 6-0,6-4 |
| ITF M25 Kassel | 2023/07/11 09:30 | Dominik Recek v Karlo Cubelic | 2-6,1-6 |
| ITF M25 Marburg | 2023/07/05 10:55 | Karlo Cubelic v Louis Wessels | 7-6,4-6,3-6 |
| ITF M25 Marburg | 2023/07/04 07:55 | Tomas Lanik v Karlo Cubelic | 3-6,6-1,7-10 |
| ITF M25 Esch/Alzette Qual | 2023/07/16 08:00 | Jim Hendrikx v Tim Pauly | 6-4,6-0 |
| ITF M25 Esch/Alzette | 2023/07/09 08:00 | Tim Pauly v Thorben Sannen | 0-6,4-6 |