Stadium: Court 8 Round: 54 Ground: Hardcourt outdoor
| ITF Women Makinohara | 2018/10/11 00:30 | Ayumi Koshiishi v Michika Ozeki | 2-6,0-6 |
| ITF Women Nonthaburi | 2018/08/05 04:15 | Michika Ozeki v Ayumi Koshiishi | 7-6,5-7,3-6 |
| ITF W25 Goyang | 2019/05/21 01:00 | Chang Liu v Ayumi Koshiishi | 6-3,4-6,10-8 |
| ITF W25 Goyang | 2019/05/20 01:00 | Hyeran Yun v Ayumi Koshiishi | 4-6,3-6 |
| ITF W25 Changwon | 2019/05/14 01:00 | Ayumi Koshiishi v Dabin Oh | 6-3,3-6,5-10 |
| ITF W25 Changwon | 2019/05/13 01:00 | Ayumi Koshiishi v Si On Park | 6-0,6-1 |
| ITF W60 Fukuoka | 2019/05/06 01:00 | Mai Hontama v Ayumi Koshiishi | 3-6,6-3,10-2 |
| ITF W25 Hong Kong | 2019/04/08 02:00 | Ayumi Koshiishi v Mihika Yadav | 6-3,2-6,4-10 |
| ITF W25 Jackson | 2019/04/03 16:40 | Ayumi Koshiishi v Ann Li | 1-6,2-6 |
| ITF W25 Jackson | 2019/04/02 15:00 | Ayumi Koshiishi v Alesya Yakubovich | 6-3,6-2 |
| ITF W25 Karuizawa | 2019/05/22 01:00 | Mei Yamaguchi v Michika Ozeki | 6-2,6-3 |
| ITF W25 Karuizawa | 2019/05/21 04:00 | Michika Ozeki v Erika Matsuda | 6-1,6-1 |
| ITF W60 Kurume | 2019/05/13 05:20 | Yuki Naito v Michika Ozeki | 6-4,6-1 |
| ITF W60 Kurume | 2019/05/13 01:50 | Meina Aratake v Michika Ozeki | 0-6,0-6 |
| ITF W60 Fukuoka | 2019/05/06 02:25 | Alexandra Bozovic v Michika Ozeki | 6-3,2-6,10-8 |
| ITF W25 Osaka | 2019/04/09 04:10 | Rebecca Marino v Michika Ozeki | 6-3,6-0 |
| ITF W25 Osaka | 2019/04/08 04:30 | Michika Ozeki v Ramu Ueda | 3-6,6-1,10-5 |
| ITF W25 Osaka | 2019/04/08 01:00 | Michika Ozeki v Chinatsu Shimizu | 6-3,5-7,10-3 |