Woong Sun Jun defeated Yaoki Ishii 6-4 6-4 in the Japan F6 round of 16 on clay. The upset overturned the form book — Yaoki Ishii came in leading the head-to-head 1–0. Woong Sun Jun claimed a first win over Yaoki Ishii in two meetings, narrowing the head-to-head to 1–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2006-04-10 | Japan F1 | R16 | hard | Yaoki Ishii | 6-4 7-5 |
Averages over each player's completed matches in the selected window. ATP, WTA & Challenger.