

Madison Keys defeated Sloane Stephens 7-6 4-6 6-2 in the Charleston quarter-final on clay. The result followed the form book — Madison Keys came in ranked #23, defending last year's semi-final. Madison Keys narrowed the head-to-head to 5–2.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2021-08-30 | US Open | R128 | hard | Sloane Stephens | 6-3 1-6 7-6(7) |
| 2021-05-10 | Rome | R64 | clay | Madison Keys | 4-6 6-2 7-5 |
| 2021-04-05 | Charleston 1 | R32 | clay | Sloane Stephens | 6-4 6-4 |
| 2018-05-28 | Roland Garros | SF | clay | Sloane Stephens | 6-4 6-4 |
| 2017-08-28 | US Open | F | hard | Sloane Stephens | 6-3 6-0 |
| 2015-03-23 | Miami | R64 | hard | Sloane Stephens | 6-4 6-2 |
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 (200 vs 200). ATP, WTA & Challenger.
Performance in the biggest moments — break points, deciding sets and tiebreaks (0–100, higher is better). About
Keys M.: 7 days rest · 1 match, 23 games (7d). Higher means fresher. About