Yaoki Ishii defeated Oh Hee Kwon 6-2 6-2 in the Japan F3 semi-final on hard. The result followed the form book — Yaoki Ishii came in leading the head-to-head 3–1. Yaoki Ishii extended the head-to-head to 4–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2006-08-07 | Indonesia F2 | F | hard | Yaoki Ishii | 6-1 7-6(2) |
| 2006-04-10 | Japan F1 | SF | hard | Oh Hee Kwon | 6-1 2-6 7-5 |
| 2005-04-25 | Japan F3 | QF | carpet | Yaoki Ishii | 3-6 6-1 6-3 |
| 1999-10-25 | Japan F6 | R16 | carpet | Yaoki Ishii | 6-2 6-2 |