Stadium: Court 5 Round: 25 Ground: Hardcourt outdoor
| ITF M15 Nishi-Tokyo | 2019/03/16 01:00 | Takuto Niki v Shuichi Sekiguchi | 4-6,7-6,3-6 |
| ITF M15 Tsukuba | 2019/03/28 02:10 | Ryohei Tagata v Takuto Niki | 3-6,6-2,7-5 |
| ITF M15 Tsukuba | 2019/03/27 01:00 | Takuto Niki v Takashi Saito | 6-4,6-2 |
| ITF M15 Kofu | 2019/03/23 01:00 | Takuto Niki v Sho Shimabukuro | 5-7,3-6 |
| ITF M15 Kofu | 2019/03/22 02:05 | Takuto Niki v Hiroyasu Ehara | 6-3,6-4 |
| ITF M15 Kofu | 2019/03/21 04:40 | Takuto Niki v Sho Katayama | 4-6,7-6,6-4 |
| ITF M15 Kofu | 2019/03/20 01:00 | Hong Kit Wong v Takuto Niki | 6-3,4-6,2-6 |
| ITF M15 Nishi-Tokyo | 2019/03/16 01:00 | Takuto Niki v Shuichi Sekiguchi | 4-6,7-6,3-6 |
| ITF M15 Nishi-Tokyo | 2019/03/15 01:00 | Takuto Niki v Yuta Shimizu | 7-6,1-6,6-3 |
| ITF M15 Nishi-Tokyo | 2019/03/17 02:00 | Shuichi Sekiguchi v Seong Chan Hong | 6-7,4-6 |
| ITF M15 Nishi-Tokyo | 2019/03/16 01:00 | Takuto Niki v Shuichi Sekiguchi | 4-6,7-6,3-6 |
| ITF M15 Nishi-Tokyo | 2019/03/15 01:00 | Shuichi Sekiguchi v Shintaro Imai | 6-3,6-0 |
| ITF M15 Nishi-Tokyo | 2019/03/14 03:45 | Shuichi Sekiguchi v Yuki Mochizuki | 6-2,6-1 |
| ITF M15 Nishi-Tokyo | 2019/03/13 01:00 | Shuichi Sekiguchi v Keisuke Saitoh | 6-3,6-2 |
| ITF M25 Mildura | 2019/03/09 01:00 | Shuichi Sekiguchi v Brydan Klein | 7-6,1-6,1-6 |
| ITF M25 Mildura | 2019/03/08 02:40 | Yuta Shimizu v Shuichi Sekiguchi | 3-6,3-6 |
| ITF M25 Mildura | 2019/03/07 02:00 | Issei Okamura v Shuichi Sekiguchi | 3-6,6-3,2-6 |