Klara Koukalova defeated Roberta Vinci 7-5 7-6 in the Portoroz quarter-final on hard. The upset overturned the form book — Roberta Vinci came in leading the head-to-head 3–0. Klara Koukalova claimed a first win over Roberta Vinci in four meetings, narrowing the head-to-head to 3–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2011-07-04 | Budapest | SF | clay | Roberta Vinci | 6-4 6-4 |
| 2006-07-17 | Palermo | R16 | clay | Roberta Vinci | 6-2 7-6 |
| 2005-10-16 | Zurich | Q16 | hard | Roberta Vinci | 6-2 6-2 |
Averages over each player's completed matches in the selected window (81 vs 200). ATP, WTA & Challenger.
Performance in the biggest moments — break points, deciding sets and tiebreaks (0–100, higher is better). About
Each player's serve crossed against the other's return, converted to expected hold of serve. Recent completed matches, ATP, WTA & Challenger. About