Bogota · SF · Clay · 10 Apr 2021
Harmony Tan v Camila Osorio
48–72 in points · Camila Osorio won
Why it went the way it did
Camila Osorio won 13.5 more points than Harmony Tan relative to what the serve alone predicted. Harmony Tan's biggest leaks: backhand execution −4.5, slice shot selection −3.2, net execution −2.7.
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 | Harmony Tan | Camila Osorio | ||||||
|---|---|---|---|---|---|---|---|---|
| Dir | Sel | Exec | Total | Dir | Sel | Exec | Total | |
| Serve 1st | −0.2 | ±0.0 | −2.3 | −2.5 | −0.4 | ±0.0 | −1.9 | −2.3 |
| Serve 2nd | ±0.0 | ±0.0 | −0.4 | −0.3 | −0.1 | ±0.0 | −0.2 | −0.3 |
| Return | ±0.0 | +0.1 | −2.5 | −2.4 | +0.1 | −0.6 | +2.3 | +1.8 |
| Forehand | −0.1 | +1.2 | −1.0 | +0.1 | −0.2 | +1.4 | −2.0 | −0.8 |
| Backhand | +0.1 | −0.5 | −4.5 | −4.9 | +0.1 | +0.1 | +1.4 | +1.7 |
| Slice | +0.2 | −3.2 | −2.3 | −5.4 | ±0.0 | −4.7 | +1.3 | −3.4 |
| Net | +0.1 | +0.5 | −2.7 | −2.1 | ±0.0 | ±0.0 | +0.4 | +0.4 |
| Touch | +0.2 | −0.1 | −0.6 | −0.5 | −0.1 | −1.5 | −0.6 | −2.2 |
| Other | ±0.0 | −0.1 | −0.5 | −0.6 | ±0.0 | ±0.0 | ±0.0 | ±0.0 |
| All shots | +0.2 | −2.0 | −16.7 | −18.6 | −0.4 | −5.3 | +0.7 | −5.1 |
Set by set
| Set | Harmony Tan | Camila Osorio | Net, Harmony | |
|---|---|---|---|---|
| 1 | −7.2 | +0.3 | −7.5 | |
| 2 | −11.4 | −5.4 | −6.0 |
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.
Harmony Tan serving
| Set | Wide | Body | T |
|---|---|---|---|
| 1 | 33% 42% | 33% 50% | 33% 17% |
| 2 | 44% 36% | 22% 57% | 34% 36% |
Set to set −0.35 per 100 first serves in sets 2+
Within sets −0.71 per 100 first serves, every two to three service games
Camila Osorio serving
| Set | Wide | Body | T |
|---|---|---|---|
| 1 | 26% 20% | 37% 86% | 37% 57% |
| 2 | 25% 63% | 41% 69% | 34% 45% |
Within sets +1.80 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.
Harmony Tan
5.1 points left on the table across 205 shots 2.47 per 100 shots
- Rally, shots 5–8: lob to your middle hit BH crosscourt ×2; BH down the line rates higher · 0.40 pts
- Return of a 2nd serve, body, deuce court hit FH through the middle ×3; FH down the line rates higher · 0.21 pts
- Serve +1: deep return to your middle hit BH through the middle ×5; BH crosscourt rates higher · 0.21 pts
- Return of a 2nd serve, wide, deuce court hit FH through the middle ×4; FH crosscourt rates higher · 0.19 pts
Camila Osorio
6.2 points left on the table across 215 shots 2.87 per 100 shots
- Rally, shots 5–8: drive to your backhand side hit BH slice through the middle ×6; BH slice crosscourt rates higher · 0.36 pts
- Return of a 2nd serve, body, deuce court hit FH through the middle ×5; FH down the line rates higher · 0.35 pts
- Serve +1: deep return to your middle hit FH through the middle ×5; FH crosscourt rates higher · 0.30 pts
- Return +1: drive to your backhand side hit BH slice through the middle ×4; BH slice crosscourt rates higher · 0.26 pts