Yumi Nakano defeated Ai Koga 6-4 6-1 in the Mie 10K round of 32 on carpet. The upset overturned the form book — Ai Koga came in leading the head-to-head 1–0. Yumi Nakano claimed a first win over Ai Koga in two meetings, narrowing the head-to-head to 1–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2012-07-23 | New Orleans LA 10K | R32 | hard | Ai Koga | 6-4 6-4 |