Alexander Flock defeated Marcel Zimmermann 7-6 6-4 in the Portugal F4 qualifying round on clay. The upset overturned the form book — Marcel Zimmermann came in leading the head-to-head 1–0. Alexander Flock claimed a first win over Marcel Zimmermann in two meetings, narrowing the head-to-head to 1–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2010-10-18 | Croatia F7 | QF | clay | Marcel Zimmermann | 3-6 6-4 6-3 |