Round: 25 Ground: Hardcourt outdoor
| ITF Women Kofu Qual | 2017/06/12 02:30 | Reina Takahashi v Kumi So | 6-1,6-0 |
| ITF Women Kofu Qual | 2017/06/11 04:00 | Reina Takahashi v Michiru Furuya | 6-1,6-2 |
| ITF Women Kofu Qual | 2017/06/11 00:00 | Nagi Hanatani v Reina Takahashi | 6-4,6-7,2-6 |
| ITF Women Tokyo Qual | 2017/06/04 02:15 | Reina Takahashi v Kwan Yau Ng | 3-6,4-6 |
| ITF Women Karuizawa Qual | 2017/05/21 02:30 | Reina Takahashi v Chihiro Takayama | 6-7,3-6 |
| ITF Women Karuizawa Qual | 2017/05/20 01:00 | Funa Kozaki v Reina Takahashi | 3-6,4-6 |
| ITF Women Kurume Qual | 2017/05/14 00:30 | Reina Takahashi v Shiho Hisamatsu | 3-6,7-6,6-7 |
| ITF Women Kofu Qual | 2017/03/27 02:30 | Reina Takahashi v Ayaka Kanai | 6-4,6-3 |
| French Open Women Qual | 2017/05/23 11:05 | Tereza Martincova v Riko Sawayanagi | 6-4,6-3 |
| ITF Women Kurume | 2017/05/19 02:10 | Erina Hayashi v Riko Sawayanagi | 6-1,1-6,6-3 |
| ITF Women Kurume | 2017/05/18 02:25 | Olivia Tjandramulia v Riko Sawayanagi | 6-4,0-6,3-6 |
| ITF Women Kurume | 2017/05/16 03:05 | Mihoki Miyahara v Riko Sawayanagi | 3-6,3-6 |
| ITF Women Fukuoka | 2017/05/11 01:00 | Varatchaya Wongteanchai v Riko Sawayanagi | 7-5,6-4 |
| ITF Women Fukuoka | 2017/05/10 03:55 | Yukina Saigo v Riko Sawayanagi | 0-6,6-4,2-6 |
| ITF Women Gifu | 2017/05/03 01:00 | Riko Sawayanagi v Arina Rodionova | 6-2,3-6,5-7 |
| WTA Zhengzhou | 2017/04/19 06:20 | Shuai Peng v Riko Sawayanagi | 6-1,6-4 |