Stadium: WSG Grandstand Round: 45 Ground: Clay
| ITF Belgium F7 | 2018/08/09 09:20 | Takashi Saito v Benjamin Pietri | 6-7,4-6 |
| ITF Belgium F7 | 2018/08/07 16:35 | Takashi Saito v Vadym Ursu | 6-7,6-3,7-6 |
| ITF Germany F10 | 2018/07/31 10:00 | Manuel Guinard v Takashi Saito | 7-6,0-6,6-1 |
| Challenger - Tampere | 2018/07/21 11:05 | Ivan Gakhov v Takashi Saito | 6-1,6-3 |
| Challenger Scheveningen Qual | 2018/07/14 10:00 | Takashi Saito v Alejandro Davidovich Fokina | 3-6,2-6 |
| ITF Japan F8 | 2018/06/13 02:25 | Takashi Saito v Kousuke Ogura | 6-2,4-6,6-1 |
| ITF Japan F7 | 2018/06/10 01:00 | Takashi Saito v Rio Noguchi | 6-3,6-4 |
| ITF Japan F7 | 2018/06/09 03:20 | Takashi Saito v Gengo Kikuchi | 4-6,7-6,6-3 |
| Challenger Pullach Qual | 2018/08/04 15:55 | Alexandre Muller v Johannes Haerteis | 7-6,7-5 |
| Challenger Sopot Qual | 2018/07/29 09:00 | Roberto Marcora v Johannes Haerteis | 6-4,7-5 |
| Challenger Sopot Qual | 2018/07/28 10:40 | Johannes Haerteis v Kamil Gajewski | 6-3,6-2 |
| ITF Austria F3 | 2018/07/19 15:00 | Johannes Haerteis v Nerman Fatic | 2-6,6-7 |
| ITF Austria F3 | 2018/07/18 09:30 | Mariano Kestelboim v Johannes Haerteis | 2-6,7-5,2-6 |
| ITF Austria F3 | 2018/07/17 13:15 | Gabriel Huber v Johannes Haerteis | 2-6,1-6 |
| ITF Austria F2 | 2018/07/14 12:00 | Nerman Fatic v Johannes Haerteis | 1-6,6-3,6-1 |
| ITF Austria F2 | 2018/07/13 12:40 | Johannes Haerteis v Eduardo Dischinger | 6-1,1-6,6-3 |