Magdalena Rybarikova defeated Simona Halep 6-2 4-6 6-3 in the New Haven round of 16 on hard. The upset overturned the form book — Simona Halep came in leading the head-to-head 4–0, defending the title, but Magdalena Rybarikova had been the form player, winning 3 of their last 5 on hard. Magdalena Rybarikova claimed a first win over Simona Halep in five meetings, narrowing the head-to-head to 4–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2018-04-23 | Stuttgart | R16 | clay | Simona Halep | 4-6 6-2 6-3 |
| 2017-10-02 | Beijing | R32 | hard | Simona Halep | 6-1 2-1 RET |
| 2017-08-07 | Toronto | R32 | hard | Simona Halep | 6-3 6-4 |
| 2013-10-14 | Moscow | R16 | hard | Simona Halep | 6-2 0-0 RET |
Averages from each player's recent completed matches (20 vs 20). ATP, WTA & Challenger.