Remi Tezuka defeated Seiko Okamoto 6-4 6-3 in the Lachine 10K round of 16 on clay. The upset overturned the form book — Seiko Okamoto came in leading the head-to-head 2–1. Remi Tezuka narrowed the head-to-head to 2–2.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2010-03-22 | Kofu 10K | R32 | hard | Remi Tezuka | 6-3 6-4 |
| 2008-04-21 | Incheon 25K | R32 | hard | Seiko Okamoto | 6-3 6-4 |
| 1999-09-06 | Ibaraki 2 10K | QF | hard | Seiko Okamoto | 6-4 6-4 |