Mari Inoue defeated Ayumi Oka 6-4 6-0 in the Komoro 25K round of 16 on clay. The upset overturned the form book — Ayumi Oka came in leading the head-to-head 1–0. Mari Inoue claimed a first win over Ayumi Oka in two meetings, narrowing the head-to-head to 1–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2009-09-21 | Makinohara 25K | R32 | carpet | Ayumi Oka | 7-5 6-1 |