Yasufumi Yamamoto defeated Tetsuya Chaen 6-4 6-2 in the Japan 1 Masters 4 round of 32 on hard. The upset overturned the form book — Tetsuya Chaen came in leading the head-to-head 3–0. Yasufumi Yamamoto claimed a first win over Tetsuya Chaen in four meetings, narrowing the head-to-head to 3–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2000-07-17 | Indonesia F3 | R32 | hard | Tetsuya Chaen | 6-1 6-2 |
| 1997-11-17 | Japan 2 Masters 2 | F | hard | Tetsuya Chaen | 6-2 3-6 6-2 |
| 1997-08-25 | Indonesia Masters 1 | R32 | hard | Tetsuya Chaen | 6-4 4-6 6-2 |
Averages over each player's completed matches in the selected window (1 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