Estelle Guisard defeated Angelique Kerber 6-4 7-6 in the Helsinki 25K round of 16 on hard. The upset overturned the form book — Angelique Kerber came in leading the head-to-head 1–0. Estelle Guisard claimed a first win over Angelique Kerber in two meetings, narrowing the head-to-head to 1–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2009-10-12 | Joue-Les-Tours 50K | R32 | hard | Angelique Kerber | 6-1 6-1 |
Averages over each player's completed matches in the selected window. ATP, WTA & Challenger.