| ITF Turkey F18 | 05/10 07:00 | 25 | Goran Markovic v Valentin Guenther | Retired | |
| ITF Turkey F18 | 05/08 07:00 | 62 | Alexander Babanine v Valentin Guenther | 3-6,3-6 | |
| ITF Turkey F18 | 05/07 09:00 | 62 | Valentin Guenther v Ivan Krivic | 6-3,6-4 | |
| ITF Turkey F18 | 05/06 06:30 | 62 | Valentin Guenther v Daniel Czepielewski | 7-6,6-2 | |
| ITF Turkey F17 | 05/01 07:30 | 62 | Sebastian Prechtel v Valentin Guenther | 6-3,6-2 | |
| ITF Turkey F17 | 04/30 07:00 | 62 | Valentin Guenther v Juan Martin | 6-4,6-3 | |
| ITF Turkey F17 | 04/29 09:00 | 62 | Daniel Czepielewski v Valentin Guenther | 4-6,1-6 | |
| ITF Greece F4 | 03/25 09:30 | 62 | Valentin Guenther v Andrea Bolla | 6-4,4-6,4-6 | |
| ITF Greece F3 | 03/21 09:25 | 25 | Benjamin Bonzi v Valentin Guenther | 6-4,5-7,6-0 | |
| ITF Greece F3 | 03/20 07:30 | 62 | Valentin Guenther v Imran Aswat | 6-3,6-2 | |
| ITF Greece F3 | 03/19 10:00 | 62 | Sergei Pogosian v Valentin Guenther | 4-6,1-6 | |
| ITF Greece F2 Qual | 03/11 10:00 | 62 | Petar Conkic v Valentin Guenther | 6-2,6-2 | |
| ITF Switzerland F1 Qual | 02/05 11:30 | 62 | Valentin Guenther v Ugo Humbert | 6-3,3-6,2-6 | |
| ITF Germany F3 | 01/23 16:20 | 44 | Hiroyasu Ehara v Valentin Guenther | Retired | |
| ITF Germany F3 | 01/23 08:30 | 44 | Valentin Guenther v Matvey Khomentovskiy | 5-7,7-6,6-3 | |
| ITF Germany F3 | 01/22 11:30 | 44 | Moritz Hoffmann v Valentin Guenther | 3-6,7-6,3-6 | |
| ITF Germany F2 Qual | 01/15 12:00 | 62 | Valentin Guenther v Jannis Kahlke | 3-6,6-7 | |
| ITF Germany F1 | 01/10 13:00 | 25 | Valentin Guenther v Yaraslau Shyla | 4-6,4-6 | |
| ITF Germany F1 Qual | 01/09 14:10 | 44 | Jurij Rodionov v Valentin Guenther | 7-6,4-6,4-6 | |
| ITF Germany F1 Qual | 01/08 13:00 | 44 | Valentin Guenther v Maximilien Sanson | 6-2,6-2 | |
| ITF Germany F17 | 11/02 10:00 | 25 | Lucas Catarina v Valentin Guenther | 6-4,7-6 | |
| ITF Germany F17 | 10/31 09:00 | 44 | Jannis Kahlke v Valentin Guenther | 3-6,0-6 | |
| ITF Germany F17 | 10/30 11:00 | 44 | Valentin Guenther v Boris Butulija | 6-3,6-0 | |
| ITF Germany F17 | 10/30 09:00 | 44 | Raphael Calzi v Valentin Guenther | 6-4,3-6,3-6 | |
| ITF Germany F16 | 10/24 10:00 | 44 | Christopher Heyman v Valentin Guenther | 6-7,6-3,6-3 | |
| ITF Germany F16 | 10/23 10:30 | 44 | Valentin Guenther v Maciej Nowak | 6-3,6-2 | |
| ITF Germany F16 | 10/23 07:30 | 44 | Matthew Hingley v Valentin Guenther | 1-6,2-6 | |
| ITF Germany F15 | 10/15 08:00 | 62 | Valentin Guenther v Gabriel Schmidt | 4-6,4-6 | |
| ITF Germany F14 | 10/09 07:00 | 44 | Valentin Guenther v Bart Van Den Berg | 6-7,3-6 | |
| ITF Germany F13 | 10/04 07:30 | 25 | Valentin Guenther v Lukas Ollert | 5-7,3-6 |