Issei Okamura defeated Keita Koyama 7-6 7-6 in the Japan F4 round of 16 on hard. Issei Okamura extended the head-to-head to 2–0.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2013-07-01 | Japan F8 | R32 | hard | Issei Okamura | 6-1 |
Averages over each player's completed matches in the selected window (200 vs 1). ATP, WTA & Challenger.
Each player's serve crossed against the other's return, converted to expected hold of serve. Recent completed matches, ATP, WTA & Challenger. Small sample — read as indicative. About