Stadium: B & B Court Round: 46 Ground: Clay
| Meerbusch, Allemagne, Qualifications | 2018/08/11 11:45 | Mats Rosenkranz v Sieber, Marc | 3-6,3-6 |
| Challenger Pullach Qual | 2018/08/04 09:00 | Sieber, Marc v Lenz, Julian | 4-6,6-4,4-6 |
| Challenger Liberec Qual | 2018/07/29 08:30 | Sieber, Marc v Marvin Moeller | 2-6,5-7 |
| Challenger Liberec Qual | 2018/07/28 08:00 | Juan Pablo Ficovich v Sieber, Marc | 3-6,6-3,3-6 |
| Challenger - Prague | 2018/07/24 11:30 | Nedovyesov, Aleksandr v Sieber, Marc | 6-0,6-4 |
| Challenger Prague Qual | 2018/07/23 10:10 | Torebko, Peter v Sieber, Marc | 1-6,4-6 |
| Challenger Prague Qual | 2018/07/22 14:10 | Dominik Kellovsky v Sieber, Marc | 3-6,6-7 |
| Challenger - Prague | 2018/07/21 14:05 | Perchicot, Mathieu v Sieber, Marc | 6-1,2-6,3-6 |
| Meerbusch, Allemagne, Qualifications | 2018/08/11 12:30 | Adrian Oetzbach v Toledo Bague, Pol | 6-4,4-6,6-2 |
| ITF Germany F11 | 2018/08/08 16:00 | Mats Rosenkranz v Adrian Oetzbach | 6-4,7-5 |
| ITF Germany F11 | 2018/08/07 11:20 | Adrian Oetzbach v Kopeinigg, Daniel | 7-5,1-6,6-4 |
| ITF Germany F10 | 2018/08/01 15:00 | Frawley, James v Adrian Oetzbach | 6-2,7-6 |
| ITF Germany F9 | 2018/07/22 11:00 | Adrian Oetzbach v Ehrat, Sandro | 4-6,3-6 |
| ITF Germany F9 | 2018/07/22 08:00 | Adrian Oetzbach v Eckert, Gilles | 6-3,6-4 |
| ITF Belgium F4 | 2018/07/16 08:00 | Adrian Oetzbach v Franco Emanuel Egea | 6-7,2-6 |
| ITF Germany F6 | 2018/07/01 13:00 | Adrian Oetzbach v Kijametovic, Aziz | 2-6,3-6 |