Joannette Kruger defeated Irina Spirlea 3-6 6-2 6-4 in the San Diego round of 32 on hard. The upset overturned the form book — Irina Spirlea came in leading the head-to-head 2–0, defending last year's round of 16. Joannette Kruger claimed a first win over Irina Spirlea in three meetings, narrowing the head-to-head to 2–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 1998-02-03 | Tokyo | R16 | hard | Irina Spirlea | 6-1 6-2 |
| 1997-01-13 | Australian Open | R64 | hard | Irina Spirlea | 6-1 6-1 |
Averages over each player's completed matches in the selected window. ATP, WTA & Challenger.