Chisayo Ito defeated Seiko Okamoto 6-7 6-3 7-6 in the Kofu 10K round of 32 on carpet. The upset overturned the form book — Seiko Okamoto came in leading the head-to-head 3–1, but Chisayo Ito had been the form player, winning 4 of their last 6 on carpet. Chisayo Ito narrowed the head-to-head to 3–2.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2002-05-20 | Tianjin 25K | R16 | hard | Seiko Okamoto | 6-4 7-5 |
| 2001-11-12 | Haibara 10K | QF | carpet | Seiko Okamoto | 5-4 |
| 2000-08-28 | Kugayama 10K | R32 | hard | Seiko Okamoto | 2-6 6-4 6-4 |
| 1999-09-06 | Ibaraki 3 10K | R16 | hard | Chisayo Ito | 6-1 4-6 6-3 |