Heather Watson defeated Polona Hercog 6-2 6-3 in the Monterrey round of 16 on hard. The upset overturned the form book — Polona Hercog came in ranked #228, defending last year's round of 16. Heather Watson extended the head-to-head to 2–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2015-04-27 | Prague | R32 | clay | Polona Hercog | 7-5 3-6 7-6(5) |
| 2012-10-08 | Osaka | R32 | hard | Heather Watson | 6-4 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
Averages over each player's completed matches in the selected window (199 vs 200). ATP, WTA & Challenger.