Sandrine Testud defeated Serena Williams 6-3 1-6 6-1 in the Filderstadt quarter-final on hard. The upset overturned the form book — Serena Williams came in leading the head-to-head 5–2. Sandrine Testud narrowed the head-to-head to 5–3.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2001-10-30 | WTA Tour Championships | SF | carpet | Serena Williams | 6-3 6-0 |
| 2001-08-13 | Toronto | QF | hard | Serena Williams | 6-0 6-2 |
| 1999-10-04 | Filderstadt | R16 | hard | Sandrine Testud | 3-6 6-4 7-5 |
| 1999-03-05 | Indian Wells | SF | hard | Serena Williams | 7-5 6-0 |
| 1999-01-18 | Australian Open | R32 | hard | Sandrine Testud | 6-2 2-6 9-7 |
| 1998-08-10 | Manhattan Beach | R16 | hard | Serena Williams | 6-4 3-6 6-1 |
| 1998-01-11 | Sydney | R16 | hard | Serena Williams | 7-6 3-0 RET |
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
Averages over each player's completed matches in the selected window (1 vs 199). ATP, WTA & Challenger.