Stadium: Court 10 Round: 25 Ground: Hardcourt outdoor
| ITF Japan F3 | 2016/03/22 03:30 | Tanuma, Ryota v Sekiguchi, Shuichi | 6-4,1-6,2-6 |
| ITF - M15 Kashiwa | 2019/04/01 00:00 | Tanuma, Ryota v Seita Watanabe | 3-6,6-1,12-10 |
| ITF - M15 Kashiwa | 2019/04/01 00:00 | Tanuma, Ryota v Tamaki Yamao | 6-7,4-6 |
| ITF - M15 Tsukuba | 2019/03/28 01:00 | Tanuma, Ryota v Shintaro Imai | 5-7,3-6 |
| ITF - M15 Tsukuba | 2019/03/26 01:00 | Aoran Wang v Tanuma, Ryota | 6-7,5-7 |
| Kofu, Qualifications Simples M-ITF-JPN-03A | 2019/03/23 02:55 | Jumpei Yamasaki v Tanuma, Ryota | 6-2,6-4 |
| Kofu, Qualifications Simples M-ITF-JPN-03A | 2019/03/22 02:00 | Issei Okamura v Tanuma, Ryota | 4-6,2-6 |
| Kofu, Qualifications Simples M-ITF-JPN-03A | 2019/03/21 04:15 | Tanuma, Ryota v Takeuchi, Kento (1987) | 6-4,6-4 |
| Kofu, Qualifications Simples M-ITF-JPN-03A | 2019/03/20 01:00 | Tanaka, Yunosuke v Tanuma, Ryota | 6-2,3-6,4-6 |
| ITF - M15 Kashiwa | 2019/04/03 05:20 | Niki, Takuto v Sekiguchi, Shuichi | 2-6,6-3,7-6 |
| ITF - M15 Nishi-Tokyo | 2019/03/17 02:00 | Sekiguchi, Shuichi v Hong, Seong Chan | 6-7,4-6 |
| ITF - M15 Nishi-Tokyo | 2019/03/16 01:00 | Niki, Takuto v Sekiguchi, Shuichi | 4-6,7-6,3-6 |
| ITF - M15 Nishi-Tokyo | 2019/03/15 01:00 | Sekiguchi, Shuichi v Shintaro Imai | 6-3,6-0 |
| ITF - M15 Nishi-Tokyo | 2019/03/14 03:45 | Sekiguchi, Shuichi v Yuki Mochizuki | 6-2,6-1 |
| ITF - M15 Nishi-Tokyo | 2019/03/13 01:00 | Sekiguchi, Shuichi v Keisuke Saitoh | 6-3,6-2 |
| ITF - M25 Mildura | 2019/03/09 01:00 | Sekiguchi, Shuichi v Klein, Brydan | 7-6,1-6,1-6 |
| ITF - M25 Mildura | 2019/03/08 02:40 | Yuta Shimizu v Sekiguchi, Shuichi | 3-6,3-6 |