Andre Wiesler defeated Marc Sieber 6-4 6-2 in the Germany F15 qualifying round on clay. The upset overturned the form book — Marc Sieber came in leading the head-to-head 2–0. Andre Wiesler claimed a first win over Marc Sieber in three meetings, narrowing the head-to-head to 2–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2008-08-18 | Germany F16 | R16 | clay | Marc Sieber | 6-2 7-5 |
| 2006-08-21 | Germany F13 | R32 | clay | Marc Sieber | 7-6(3) 7-5 |
Averages over each player's completed matches in the selected window. ATP, WTA & Challenger.