Yoon Jeong Cho defeated Keiko Nagatomi 6-4 6-3 in the Seoul 50K round of 32 on hard. The upset overturned the form book — Keiko Nagatomi came in leading the head-to-head 1–0. Yoon Jeong Cho claimed a first win over Keiko Nagatomi in two meetings, narrowing the head-to-head to 1–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 1999-04-26 | Gifu 50K | R32 | carpet | Keiko Nagatomi | 3-6 6-4 6-0 |
Averages over each player's completed matches in the selected window. ATP, WTA & Challenger.