Polona Hercog defeated Katerina Siniakova 3-6 7-5 6-2 in the Stuttgart qualifying round 1 on clay. The upset overturned the form book — Katerina Siniakova came in ranked #34. Polona Hercog extended the head-to-head to 2–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2019-10-14 | Moscow | R32 | hard | Polona Hercog | 6-4 6-2 |
| 2015-04-27 | Prague | R16 | clay | Katerina Siniakova | 6-1 6-4 |
Each player's serve crossed against the other's return, converted to expected hold of serve. Recent completed matches, ATP, WTA & Challenger. About
Per-surface Serve / Return Rating (0–100, percentile within the clay field, opponent-adjusted over 52 weeks). About
Averages over each player's completed matches in the selected window (200 vs 200). ATP, WTA & Challenger.
Performance in the biggest moments — break points, deciding sets and tiebreaks (0–100, higher is better). About
Hercog P.: 1 day rest · 1 match, 26 games (7d) · Siniakova K.: 13 days rest · 1 match (14d). Higher means fresher. About