Issei Okamura advanced when Keita Koyama retired 6-1 in the Japan F8 round of 32. Issei Okamura extended the head-to-head to 2–0.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2013-04-01 | Japan F4 | R16 | hard | Issei Okamura | 7-6(4) 7-6(2) |
Averages over each player's completed matches in the selected window (25 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