Yuki Matsuo defeated Sun Yong Kim Jr 6-2 6-3 in the Japan F9 round of 32 on carpet. The upset overturned the form book — Sun Yong Kim Jr came in leading the head-to-head 1–0. Yuki Matsuo claimed a first win over Sun Yong Kim Jr in two meetings, narrowing the head-to-head to 1–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2009-08-03 | China F5 | R16 | hard | Sun Yong Kim Jr | 6-0 6-2 |