Stadium: Center A Round: 25 Ground: Hardcourt outdoor
| Matsuyama, Singles M-ITF-JPN-06A | 2019/04/09 04:10 | Tanuma, Ryota v Sekiguchi, Shuichi | 4-6,4-6 |
| ITF Japan F3 | 2016/03/22 03:30 | Tanuma, Ryota v Sekiguchi, Shuichi | 6-4,1-6,2-6 |
| Sapporo, Singles Main, M-ITF-JPN-02A | 2023/09/10 02:00 | Sekiguchi, Shuichi v Daisuke Sumizawa | 6-1,6-4 |
| Sapporo, Singles Main, M-ITF-JPN-02A | 2023/09/09 02:00 | Naoki Nakagawa v Sekiguchi, Shuichi | 7-5,3-6,5-7 |
| Sapporo, Singles Main, M-ITF-JPN-02A | 2023/09/08 02:30 | Sekiguchi, Shuichi v Jumpei Yamasaki | 6-4,6-3 |
| Sapporo, Singles Main, M-ITF-JPN-02A | 2023/09/07 01:00 | Sekiguchi, Shuichi v Chase Ferguson | 6-2,6-2 |
| Sapporo, Singles Main, M-ITF-JPN-02A | 2023/09/05 04:20 | Sekiguchi, Shuichi v Hiroki Sakagawa | 6-3,6-2 |
| Zhangjiagang, China | 2023/08/28 10:15 | Sekiguchi, Shuichi v Jie Cui | 1-6,2-6 |
| Zhangjiagang, China | 2023/08/27 06:25 | Sekiguchi, Shuichi v Alcantara, Francis Casey | 7-5,6-3 |
| Challenger Zhuhai | 2023/08/22 07:00 | Dominik Palan v Sekiguchi, Shuichi | 7-6,5-7,6-2 |
| Sapporo, Singles Main, M-ITF-JPN-02A | 2023/09/07 00:50 | Kokoro Isomura v Tanuma, Ryota | 6-4,6-3 |
| Sapporo, Singles Main, M-ITF-JPN-02A | 2023/09/05 02:00 | Tanuma, Ryota v Yunseok Jang | 6-4,7-5 |
| Challenger Matsuyama | 2022/11/06 01:00 | Tanuma, Ryota v Naoki Nakagawa | 3-6,4-6 |
| Challenger Yokohama | 2022/11/01 05:55 | Damir Dzumhur v Tanuma, Ryota | 6-3,6-1 |
| Challenger Yokohama | 2022/10/31 01:30 | Kawakami, Rimpei v Tanuma, Ryota | 6-7,6-4,4-6 |
| Challenger Seoul | 2022/10/09 06:00 | Hamad Medjedovic v Tanuma, Ryota | 6-4,6-3 |
| ATP Tokyo | 2022/10/01 07:55 | Tanuma, Ryota v Ramkumar Ramanathan | 5-7,3-6 |
| Kashiwa, Singles Main, M-ITF-JPN-03A | 2022/10/01 02:45 | Kawakami, Rimpei v Tanuma, Ryota | 6-3,6-2 |