Hiromasa Oku defeated Yohei Ono 6-2 6-4 in the Japan F7 semi-final on carpet. The upset overturned the form book — Yohei Ono came in leading the head-to-head 2–0. Hiromasa Oku claimed a first win over Yohei Ono in three meetings, narrowing the head-to-head to 2–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2013-06-10 | Japan F5 | QF | clay | Yohei Ono | 6-2 6-1 |
| 2012-06-18 | Japan F6 | R32 | grass | Yohei Ono | 6-2 5-7 7-6(4) |
Averages over each player's completed matches in the selected window. ATP, WTA & Challenger.