Serena Williams defeated Garbine Muguruza 2-6 6-3 6-2 in the Australian Open round of 16 on hard. The upset overturned the form book — Garbine Muguruza came in leading the head-to-head 3–2, defending last year's round of 16, but Serena Williams had been the form player, winning 3 of their last 6 on hard. Serena Williams narrowed the head-to-head to 3–3.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2019-03-04 | Indian Wells | R32 | hard | Garbine Muguruza | 6-3 1-0 RET |
| 2016-05-23 | Roland Garros | F | clay | Garbine Muguruza | 7-5 6-4 |
| 2015-06-29 | Wimbledon | F | grass | Serena Williams | 6-4 6-4 |
| 2014-05-26 | Roland Garros | R64 | clay | Garbine Muguruza | 6-2 6-2 |
| 2013-01-14 | Australian Open | R64 | hard | Serena Williams | 6-2 6-0 |
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 196). ATP, WTA & Challenger.
Performance in the biggest moments — break points, deciding sets and tiebreaks (0–100, higher is better). About