| DTB German Pro Series | 06/11 14:40 | 1 | [217] Oscar Otte v Lenz, Julian [251] | 3-6,6-3,3-6 | |
| DTB German Pro Series | 06/10 10:10 | 1 | Lenz, Julian v Max Wiskandt | 6-3,6-2 | |
| DTB German Pro Series | 06/09 09:25 | 1 | [251] Lenz, Julian v Kai Wehnelt [445] | 7-6,3-6,4-6 | |
| Monterrey, Mexico | 03/02 17:25 | 24 | [247] Lenz, Julian v Aleksandar Vukic [244] | 3-6,3-6 | |
| Challenger Calgary | 02/27 18:30 | 26 | [249] Lenz, Julian v Arthur Rinderknech [206] | 7-6,3-6,6-7 | |
| Challenger Calgary | 02/26 19:45 | 25 | [249] Lenz, Julian v Shintaro Imai [305] | 6-3,3-6,7-6 | |
| Challenger - Koblenz | 02/18 14:15 | 25 | [245] Lenz, Julian v Maximilian Marterer [379] | 1-6,3-6 | |
| Challenger Launceston | 02/04 04:10 | 25 | [245] Lenz, Julian v Benjamin Lock [468] | 2-6,7-5,6-7 | |
| Challenger - Burnie | 01/28 01:30 | 25 | [239] Lenz, Julian v Kavcic, Blaz [309] | 4-6,4-6 | |
| Open d'Australie | 01/14 01:55 | 44 | [168] Pedro Martinez v Lenz, Julian [236] | 6-0,6-1 | |
| Challenger Ortisei | 11/11 14:45 | 24 | [233] Lenz, Julian v Daniel Masur [252] | 6-7,6-4,3-6 | |
| Challenger Eckental | 10/30 20:30 | 25 | [238] Lenz, Julian v Emil Ruusuvuori [148] | 5-7,6-4,4-6 | |
| Challenger Eckental | 10/29 13:15 | 24 | [238] Lenz, Julian v Viktor Durasovic [341] | 7-6,6-2 | |
| Challenger - Hambourg | 10/22 08:00 | 24 | Lenz, Julian v Daniel Altmaier | Cancelled | |
| Challenger Ismaning | 10/19 14:20 | 28 | [239] Lacko, Lukas v Lenz, Julian [259] | 6-3,3-6,7-6 | |
| Challenger Ismaning | 10/18 16:35 | 27 | [259] Lenz, Julian v Haerteis, Johannes [392] | Retired | |
| Challenger Ismaning | 10/17 16:35 | 26 | [259] Lenz, Julian v Constant Lestienne [224] | 7-6,6-4 | |
| Challenger Ismaning | 10/16 15:45 | 25 | [181] Bachinger, Matthias v Lenz, Julian [259] | Retired | |
| Challenger Ismaning | 10/15 11:30 | 24 | [312] Lukas Klein v Lenz, Julian [259] | 4-6,3-6 | |
| Challenger Ismaning | 10/14 08:00 | 166 | Lenz, Julian v Schifris, Jeremy | 6-3,6-3 | |
| Nur-Sultan II, Kazakhstan | 10/02 09:50 | 25 | [164] Istomin, Denis v Lenz, Julian [264] | 7-5,6-1 | |
| Nur-Sultan II, Kazakhstan | 10/01 09:00 | 24 | Lenz, Julian v Beibit Zhukayev | 6-2,7-6 | |
| Orleans, France | 09/24 14:55 | 24 | [314] Viktor Durasovic v Lenz, Julian [264] | 6-3,7-6 | |
| Metz, France | 09/17 17:45 | 25 | [270] Lenz, Julian v Carreno-Busta, Pablo [62] | 1-6,1-6 | |
| Metz, France | 09/16 09:00 | 164 | [127] Bachinger, Matthias v Lenz, Julian [274] | 4-6,4-6 | |
| Metz, France | 09/15 12:10 | 64 | [274] Lenz, Julian v Constant Lestienne [195] | 4-6,6-3,7-5 | |
| Challenger Szczecin | 09/11 09:55 | 25 | [185] Alexey Vatutin v Lenz, Julian [274] | 6-3,6-1 | |
| Challenger Szczecin | 09/10 13:15 | 24 | [274] Lenz, Julian v Nikolas S Izquierdo [404] | 6-2,6-4 | |
| Genoa, Italy | 09/02 13:20 | 24 | [275] Lenz, Julian v Gianluca Mager [142] | 5-7,4-6 | |
| Challenger Como | 08/26 13:30 | 24 | [308] Jelle Sels v Lenz, Julian [275] | 6-3,4-6,6-3 |