Shinobu Asagoe defeated Ai Sugiyama 6-3 7-5 in the Tokyo round of 16 on hard. The upset overturned the form book — Ai Sugiyama came in leading the head-to-head 5–0, defending last year's final, but Shinobu Asagoe had been the form player, winning 1 of their last 4 on hard. Shinobu Asagoe claimed a first win over Ai Sugiyama in six meetings, narrowing the head-to-head to 5–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2004-10-18 | Zurich | R32 | hard | Ai Sugiyama | 6-2 6-3 |
| 2004-07-26 | San Diego | R32 | hard | Ai Sugiyama | 6-2 6-2 |
| 2002-09-16 | Tokyo | R32 | hard | Ai Sugiyama | 6-4 6-1 |
| 2002-02-17 | Memphis | R16 | hard | Ai Sugiyama | 6-2 7-6(3) |
| 2001-01-07 | Canberra | R32 | hard | Ai Sugiyama | 6-4 6-2 |
Each player's serve crossed against the other's return, converted to expected hold of serve. Recent completed matches, ATP, WTA & Challenger. About
Averages over each player's completed matches in the selected window (39 vs 172). ATP, WTA & Challenger.