| ITF M25 Trimbach | 03/15 11:30 | 25 | [440] Johannes Haerteis v Marcello Serafini [376] | 4-6,7-5,4-6 | |
| ITF M15 Oberhaching | 02/15 12:25 | 25 | [355] Mick Veldheer v Johannes Haerteis [464] | 3-6,6-4,6-4 | |
| ITF M25 Bath | 02/07 12:10 | 25 | George Loffhagen v Johannes Haerteis | 6-3,6-3 | |
| Challenger Koblenz | 01/31 17:35 | 25 | Alexey Vatutin v Johannes Haerteis | 7-6,6-1 | |
| Challenger Koblenz | 01/30 10:00 | 19 | Jeremy Jahn v Johannes Haerteis | 4-6,4-6 | |
| Challenger Koblenz | 01/29 13:45 | 14 | Johannes Haerteis v Andrea Arnaboldi | 6-4,6-4 | |
| ITF M25 Nussloch | 01/25 11:50 | 25 | Johannes Haerteis v Elmar Ejupovic | 5-7,6-7 | |
| Challenger Drummondville | 11/14 18:50 | 19 | Joshua Lapadat v Johannes Haerteis | Retired | |
| Challenger Drummondville | 11/13 21:25 | 14 | Evan King v Johannes Haerteis | 7-6,2-6,2-6 | |
| Challenger Calgary | 11/08 23:55 | 25 | Johannes Haerteis v Gabriel Decamps | 5-7,4-6 | |
| Challenger Calgary | 11/07 18:50 | 19 | Alafia Ayeni v Johannes Haerteis | 4-6,3-6 | |
| Challenger Calgary | 11/07 00:15 | 14 | Philip Florig v Johannes Haerteis | 3-6,2-6 | |
| ITF M15 Forbach | 09/29 08:30 | 26 | Max Hans Rehberg v Johannes Haerteis | 7-6,6-2 | |
| ITF M15 Forbach | 09/27 08:00 | 25 | Valentin Faure v Johannes Haerteis | 2-6,1-6 | |
| ITF M15 Danderyd | 09/23 10:25 | 27 | Johannes Haerteis v Vito Tonejc | 4-6,7-6,4-6 | |
| ITF M15 Danderyd | 09/22 09:35 | 26 | Johannes Haerteis v Michal Mikula | 6-7,6-2,7-5 | |
| ITF M15 Danderyd | 09/20 12:10 | 25 | Johannes Haerteis v Arvid Nordquist | 6-3,6-3 | |
| ITF M25 Roehampton | 08/23 09:00 | 25 | Johannes Haerteis v Giles Hussey | 4-6,2-6 | |
| ITF M25 Aldershot | 08/17 09:00 | 25 | Max Basing v Johannes Haerteis | 6-1,6-0 | |
| ITF M15 Metzingen | 07/22 15:45 | 27 | Johannes Haerteis v Sander Jong | 3-6,7-6,6-7 | |
| ITF M15 Metzingen | 07/21 11:00 | 26 | Johannes Haerteis v Karl Friberg | 6-4,1-6,6-3 | |
| ITF M15 Metzingen | 07/20 11:00 | 25 | Johannes Haerteis v Liam Gavrielides | 6-4,5-7,7-6 | |
| ITF M25 Marburg | 07/06 12:20 | 25 | Johannes Haerteis v Max Wiskandt | 4-6,7-6,1-6 | |
| Challenger Malaga | 06/27 08:30 | 19 | [331] Gabriel Decamps v Johannes Haerteis [439] | 6-4,6-1 | |
| Challenger Malaga | 06/26 08:30 | 14 | David Marrero v Johannes Haerteis | 2-6,6-4,1-6 | |
| ITF M25 Martos | 06/16 15:30 | 26 | [443] Johannes Haerteis v Alberto Barroso Campos [281] | 2-6,6-3,2-6 | |
| ITF M25 Martos | 06/15 17:05 | 25 | Johannes Haerteis v Aaron Cohen | 6-4,6-4 | |
| ITF M15 Cordoba | 06/08 18:40 | 25 | Svyatoslav Gulin v Johannes Haerteis | 6-4,6-2 | |
| Challenger Tunis | 05/15 09:30 | 14 | [400] Shintaro Mochizuki v Johannes Haerteis [432] | 7-5,3-6,6-1 | |
| Challenger Heilbronn | 05/09 11:35 | 19 | [432] Johannes Haerteis v Henri Squire [353] | Retired |