| UTR Pro Yokohama Women | 09/15 02:49 | - | Ayaka Kanai v Rira Kosaka | 4-6,3-6 | |
| UTR Pro Yokohama Women | 09/13 03:00 | - | Rira Kosaka v Miyu Kageyama | View | |
| UTR Pro Yokohama Women | 09/10 04:08 | - | Rira Kosaka v Yuka Matsumoto | 6-3,2-6,6-4 | |
| ITF W15 Sapporo | 07/31 05:10 | 25 | Hayu Kinoshita v Rira Kosaka | 4-6,6-1,6-4 | |
| ITF W15 Sapporo | 07/30 04:30 | 54 | Rira Kosaka v Aely Arai | 7-6,6-2 | |
| ITF W15 Sapporo | 07/30 01:00 | 54 | Mei Hasegawa v Rira Kosaka | 3-6,5-7 | |
| ITF W15 Sapporo | 07/22 10:00 | 54 | Rira Kosaka v Kanna Soeda | 1-6,7-5,5-10 |