Stadium: Court 4 Round: 46 Ground: Clay
| Challenger - Prague | 2018/07/21 13:20 | Uzhylovsky, Vladimir v Dominik Kellovsky | 6-3,2-6,3-6 |
| ITF Czech Republic F6 | 2018/07/12 10:55 | Jirousek, Tomas v Dominik Kellovsky | 6-3,7-6 |
| ITF Czech Republic F6 | 2018/07/11 10:30 | Dominik Kellovsky v Bugaj, Martin | 6-4,6-2 |
| ITF Czech Republic F6 | 2018/07/10 09:20 | Boychuk, Roman v Dominik Kellovsky | 4-6,2-6 |
| ITF Czech Republic F4 | 2018/06/25 12:05 | Dominik Kellovsky v Vit Kopriva | 6-4,3-6,0-6 |
| ITF Czech Republic F4 Qual | 2018/06/24 09:00 | Dominik Kellovsky v Daniel Paty | 6-1,6-3 |
| ITF Czech Republic F4 Qual | 2018/06/23 10:00 | Dominik Kellovsky v Fekiac, Martin | 6-0,6-1 |
| Challenger Poprad Tatry Qual | 2018/06/16 08:45 | Dominik Kellovsky v Nejedly, Pavel | 1-6,3-6 |
| Challenger - Prague | 2018/07/21 14:05 | Perchicot, Mathieu v Sieber, Marc | 6-1,2-6,3-6 |
| Germany F8, Singles | 2018/07/19 09:30 | Sieber, Marc v Heyman, Christopher | 1-6,5-7 |
| Germany F8, Singles | 2018/07/17 14:05 | Viktor Durasovic v Sieber, Marc | 3-6,2-6 |
| Challenger Caltanissetta | 2018/06/12 08:00 | Arevalo-Gonzalez, Marcelo v Sieber, Marc | 1-6,6-1,7-5 |
| Challenger Caltanissetta Qual | 2018/06/11 10:15 | Souza, Joao Olavo v Sieber, Marc | 6-2,3-6,4-6 |
| Challenger Caltanissetta Qual | 2018/06/10 11:30 | Sieber, Marc v Pawel Juszczak | 6-0,6-1 |
| Challenger Caltanissetta Qual | 2018/06/09 13:25 | Balmashev, Mikhail v Sieber, Marc | 0-6,1-6 |
| Challenger Prostejov Qual | 2018/06/03 15:25 | Sieber, Marc v Satral, Jan | 6-4,3-6,4-6 |