Martina Hingis defeated Steffi Graf 3-6 6-2 6-4 in the Tokyo quarter-final on hard. The upset overturned the form book — Steffi Graf came in leading the head-to-head 2–0. Martina Hingis claimed a first win over Steffi Graf in three meetings, narrowing the head-to-head to 2–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 1999-05-24 | Roland Garros | F | clay | Steffi Graf | 4-6 7-5 6-2 |
| 1998-11-09 | Philadelphia | QF | carpet | Steffi Graf | 6-2 4-6 6-0 |
Averages over each player's completed matches in the selected window. ATP, WTA & Challenger.