Stadium: Court 1 Round: 28 Ground: Clay
| ITF M15 Saarlouis | 2023/06/21 09:25 | Mika Brunold v Marcel Zielinski | 3-6,1-6 |
| ITF M15 Meerbusch | 2023/04/27 08:55 | Marcel Zielinski v Liam Gavrielides | 6-7,1-6 |
| ITF M15 Meerbusch | 2023/04/26 09:00 | Marcel Zielinski v John Sperle | 7-6,7-5 |
| ITF M15 Telde | 2023/04/23 09:00 | Marcel Zielinski v Alejandro Manzanera Pertusa | 4-6,6-7 |
| ITF M15 Telde | 2023/04/22 09:00 | Kai Lemstra v Marcel Zielinski | 2-6,4-6 |
| ITF M15 Telde | 2023/04/21 09:00 | Marcel Zielinski v Martin Cuevas | 6-4,6-1 |
| ITF M15 Telde | 2023/04/20 12:30 | Jorge Martinez Martinez v Marcel Zielinski | 3-6,2-6 |
| ITF M15 Telde | 2023/04/18 08:00 | Marcel Zielinski v Benjamin Winter Lopez | 3-6,6-2,6-4 |
| ITF M15 Store | 2023/06/21 14:15 | Sebastian Sorger v Andrea Guerrieri | 6-2,3-6,2-6 |
| ITF M25 Kiseljak | 2023/05/31 13:30 | Sebastian Sorger v Duje Ajdukovic | 2-6,2-6 |
| ITF M25 Kiseljak | 2023/05/30 07:30 | Sebastian Sorger v Enrique Bogo | 6-1,6-4 |
| ITF M15 Brcko | 2023/05/25 13:50 | Sebastian Sorger v Andrej Nedic | 1-6,3-6 |
| ITF M15 Doboj | 2023/05/14 12:00 | Ergi Kirkin v Sebastian Sorger | 7-6,7-5 |
| ITF M15 Doboj | 2023/05/13 13:00 | Viacheslav Bielinskyi v Sebastian Sorger | 4-6,1-6 |
| ITF M15 Doboj | 2023/05/13 09:00 | Sebastian Sorger v Mirko Martinez | 6-1,7-5 |
| ITF M15 Doboj | 2023/05/12 08:50 | Sebastian Sorger v Lucio Carnevalle | 7-6,6-2 |