Seiko Okamoto defeated Riei Kawamata 2-4 4-2 4-2 4-2 in the Haibara 10K round of 16 on clay. Seiko Okamoto extended the head-to-head to 2–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 1998-09-07 | Kugayama 1 10K | R16 | hard | Seiko Okamoto | 6-2 6-1 |
| 1998-07-13 | Qing Dao 25K | R32 | hard | Riei Kawamata | 6-2 6-2 |