Marcel Zimmermann defeated Marc Sieber 6-1 6-3 in the Turkey F1 round of 32 on clay. Marcel Zimmermann extended the head-to-head to 2–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2011-04-04 | Croatia F5 | R16 | clay | Marc Sieber | 6-1 2-0 |
| 2011-03-28 | Croatia F4 | R16 | clay | Marcel Zimmermann | 7-6(6) 0-6 6-3 |
Averages over each player's completed matches in the selected window. ATP, WTA & Challenger.