Yoon Young Jeong defeated Kai Chen Chang 7-6 1-6 6-1 in the Gimcheon 25K round of 16 on hard. The upset overturned the form book — Kai Chen Chang came in leading the head-to-head 1–0. Yoon Young Jeong claimed a first win over Kai Chen Chang in two meetings, narrowing the head-to-head to 1–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2007-11-12 | Manila 10K | QF | clay | Kai Chen Chang | 1-6 6-3 6-3 |
Averages over each player's completed matches in the selected window. ATP, WTA & Challenger.