Keita Koyama defeated Bumpei Sato 2-6 6-4 6-4 in the Japan F5 qualifying round on clay. The upset overturned the form book — Bumpei Sato came in leading the head-to-head 1–0. Keita Koyama claimed a first win over Bumpei Sato in two meetings, narrowing the head-to-head to 1–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2012-06-18 | Japan F6 | R16 | grass | Bumpei Sato | 6-1 6-1 |
Averages over each player's completed matches in the selected window (1 vs 5). 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