Seiko Okamoto defeated Yu An Chen 6-3 6-0 in the Kugayama 10K round of 32 on hard. The upset overturned the form book — Yu An Chen came in leading the head-to-head 2–0. Seiko Okamoto claimed a first win over Yu An Chen in three meetings, narrowing the head-to-head to 2–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2000-04-17 | Dalian 10K | R32 | hard | Yu An Chen | 7-6(4) 3-6 6-4 |
| 1999-09-06 | Ibaraki 2 10K | SF | hard | Yu An Chen | 6-2 6-3 |