

Sloane Stephens defeated Naomi Osaka 6-3 7-5 in the Acapulco quarter-final on hard. The upset overturned the form book — Naomi Osaka came in ranked #13. Sloane Stephens extended the head-to-head to 2–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2022-03-07 | Indian Wells | R128 | hard | Naomi Osaka | 3-6 6-1 6-2 |
| 2018-10-22 | Singapore | RR | hard | Sloane Stephens | 7-5 4-6 6-1 |
Averages over each player's completed matches in the selected window (200 vs 199). ATP, WTA & Challenger.
Performance in the biggest moments — break points, deciding sets and tiebreaks (0–100, higher is better). About
Stephens S.: 2 days rest · 4 matches, 81 games (7d) · Osaka N.: 9 days rest · 3 matches (14d). Higher means fresher. About
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 hard field, opponent-adjusted over 52 weeks). About