Arata Onozawa defeated Hiroyasu Sato 4-6 7-6 6-2 in the Japan F6 round of 16 on carpet. The upset overturned the form book — Hiroyasu Sato came in leading the head-to-head 1–0. Arata Onozawa claimed a first win over Hiroyasu Sato in two meetings, narrowing the head-to-head to 1–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2005-06-20 | Japan F7 | R32 | clay | Hiroyasu Sato | 6-4 7-6(4) |
Averages over each player's completed matches in the selected window. ATP, WTA & Challenger.