Charleston · R64 · Clay · 2 Apr 2024
Kayla Day v Caroline Dolehide
78–76 in points · Kayla Day won
Why it went the way it did
Kayla Day won 1.0 more points than Caroline Dolehide relative to what the serve alone predicted. Caroline Dolehide's biggest leaks: forehand execution −5.1, slice shot selection −2.5, return shot selection −1.2.
Each shot moves its hitter's chance of winning the point. Those moves are split into direction choice, shot selection and execution, and summed here. Read both columns together: one player's gain is the other's loss.
| Shot | Kayla Day | Caroline Dolehide | ||||||
|---|---|---|---|---|---|---|---|---|
| Dir | Sel | Exec | Total | Dir | Sel | Exec | Total | |
| Serve 1st | +0.1 | ±0.0 | +1.7 | +1.9 | −0.1 | ±0.0 | +0.3 | +0.1 |
| Serve 2nd | ±0.0 | ±0.0 | −0.7 | −0.7 | ±0.0 | ±0.0 | −0.8 | −0.8 |
| Return | +0.1 | +0.6 | +1.3 | +1.9 | −0.3 | −1.2 | +0.5 | −1.0 |
| Forehand | +0.1 | +2.7 | −0.1 | +2.7 | +0.1 | +4.6 | −5.1 | −0.4 |
| Backhand | −1.2 | +0.5 | −0.3 | −1.0 | −0.2 | +0.7 | +0.4 | +0.9 |
| Slice | −0.6 | −3.2 | −0.1 | −3.8 | +0.1 | −2.5 | +0.6 | −1.8 |
| Net | −0.4 | +0.4 | −1.8 | −1.8 | −0.3 | +0.6 | +1.0 | +1.3 |
| Touch | −0.1 | −0.5 | −0.3 | −0.9 | −0.1 | −0.9 | −0.2 | −1.2 |
| All shots | −1.9 | +0.4 | −0.3 | −1.8 | −0.7 | +1.3 | −3.4 | −2.8 |
Set by set
| Set | Kayla Day | Caroline Dolehide | Net, Kayla | |
|---|---|---|---|---|
| 1 | −3.5 | +1.2 | −4.8 | |
| 2 | +3.5 | −3.8 | +7.3 | |
| 3 | −1.8 | −0.2 | −1.6 |
Adaptation
First-serve direction mix set by set, with the share of points each direction won. The scores measure whether the server moved toward the directions that had been winning earlier in this match, set to set and every two to three service games, in points per 100 first serves. Read them as a habit, not a gain: across the tour, a direction's edge in early sets barely predicts the later ones. Whether the returner responded can't be told apart from noise within one match.
Kayla Day serving
| Set | Wide | Body | T |
|---|---|---|---|
| 1 | 39% 55% | 21% 33% | 39% 18% |
| 2 | 42% 63% | 16% 100% | 42% 63% |
| 3 | 40% 50% | 17% 100% | 43% 54% |
Set to set −0.86 per 100 first serves in sets 2+
Within sets +0.29 per 100 first serves, every two to three service games
Caroline Dolehide serving
| Set | Wide | Body | T |
|---|---|---|---|
| 1 | 56% 50% | 22% 57% | 22% 57% |
| 2 | 50% 13% | 13% 0% | 38% 50% |
| 3 | 34% 60% | 38% 73% | 28% 63% |
Set to set +1.52 per 100 first serves in sets 2+
Within sets −0.01 per 100 first serves, every two to three service games
Counterfactual: the best direction every time
If each shot had gone in the direction that is usually worth most for that stroke and position, this is how many more points each player would expect to win. It's an upper bound: the best direction isn't always on, and the chart can't see the ball's pace or position.
Kayla Day
11.9 points left on the table across 332 shots 3.58 per 100 shots
- Return of a 1st serve, T, deuce court hit FH through the middle ×3; FH inside-out rates higher · 0.65 pts
- Rally, shots 5–8: drive to your backhand side hit BH through the middle ×12; BH crosscourt rates higher · 0.52 pts
- Long rally, 9+: volley to your backhand side, opponent at net hit BH through the middle ×2; BH down the line rates higher · 0.45 pts
- Return +1: drive to your backhand side hit BH through the middle ×9; BH crosscourt rates higher · 0.43 pts
Caroline Dolehide
10.0 points left on the table across 327 shots 3.05 per 100 shots
- Rally, shots 5–8: drive to your middle hit FH through the middle ×11; FH crosscourt rates higher · 0.77 pts
- Rally, shots 5–8: drive to your backhand side hit FH through the middle ×5; FH inside-in rates higher · 0.53 pts
- Rally, shots 5–8: drive to your middle, you at net hit FH volley through the middle ×2; FH volley crosscourt rates higher · 0.48 pts
- Return +1: drive to your middle hit FH through the middle ×6; FH down the line rates higher · 0.39 pts