Keisuke Watanuki defeated Kenichi Sakakibara 6-3 6-4 in the Japan F2 qualifying round of 16 on hard. The result followed the form book — Keisuke Watanuki came in leading the head-to-head 2–0. Keisuke Watanuki extended the head-to-head to 3–0.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2015-06-08 | Japan F6 | Q16 | hard | Keisuke Watanuki | 6-2 6-1 |
| 2014-03-24 | Japan F3 | Q32 | hard | Keisuke Watanuki | 6-4 6-0 |
Averages over each player's completed matches in the selected window. ATP, WTA & Challenger.