Roland Garros · R32 · Clay · 2 Oct 2020
Kiki Bertens v Katerina Siniakova
54–31 in points · Kiki Bertens won
Why it went the way it did
Kiki Bertens won 10.4 more points than Katerina Siniakova relative to what the serve alone predicted. Katerina Siniakova's biggest leaks: forehand execution −3.0, slice shot selection −2.1, serve 2nd execution −1.1.
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 | Kiki Bertens | Katerina Siniakova | ||||||
|---|---|---|---|---|---|---|---|---|
| Dir | Sel | Exec | Total | Dir | Sel | Exec | Total | |
| Serve 1st | +0.3 | ±0.0 | +1.4 | +1.7 | −0.2 | ±0.0 | −0.7 | −0.9 |
| Serve 2nd | ±0.0 | ±0.0 | −0.2 | −0.1 | ±0.0 | ±0.0 | −1.1 | −1.1 |
| Return | ±0.0 | ±0.0 | +1.0 | +1.0 | +0.2 | −0.3 | −0.6 | −0.7 |
| Forehand | +0.9 | +1.3 | +1.5 | +3.7 | +0.1 | +1.0 | −3.0 | −1.9 |
| Backhand | −0.2 | +0.2 | +0.6 | +0.6 | +0.5 | −0.1 | −0.5 | −0.1 |
| Slice | −0.2 | −3.6 | +1.6 | −2.3 | −0.1 | −2.1 | +1.3 | −0.9 |
| Net | +0.2 | +0.2 | −0.8 | −0.5 | +0.1 | +0.1 | −0.6 | −0.4 |
| Touch | −0.1 | −1.0 | +1.5 | +0.3 | ±0.0 | −0.2 | +0.1 | ±0.0 |
| All shots | +0.9 | −3.1 | +6.6 | +4.4 | +0.6 | −1.6 | −5.0 | −6.1 |
Set by set
| Set | Kiki Bertens | Katerina Siniakova | Net, Kiki | |
|---|---|---|---|---|
| 1 | +1.9 | −4.1 | +6.0 | |
| 2 | +2.5 | −2.0 | +4.4 |
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.
Kiki Bertens serving
| Set | Wide | Body | T |
|---|---|---|---|
| 1 | 52% 79% | 7% 50% | 41% 36% |
| 2 | 45% 67% | – | 55% 82% |
Within sets −1.09 per 100 first serves, every two to three service games
Katerina Siniakova serving
| Set | Wide | Body | T |
|---|---|---|---|
| 1 | 28% 20% | 39% 29% | 33% 33% |
| 2 | 32% 50% | 32% 67% | 37% 43% |
Within sets −0.90 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.
Kiki Bertens
4.3 points left on the table across 178 shots 2.41 per 100 shots
- Rally, shots 5–8: drive to your backhand side hit BH slice through the middle ×5; BH slice crosscourt rates higher · 0.30 pts
- Long rally, 9+: drive to your backhand side hit BH through the middle ×4; BH crosscourt rates higher · 0.21 pts
- Return +1: drive to your backhand side hit BH through the middle ×4; BH crosscourt rates higher · 0.19 pts
- Rally, shots 5–8: drop shot to your backhand side, opponent at net hit BH slice crosscourt ×2; BH slice down the line rates higher · 0.18 pts
Katerina Siniakova
4.3 points left on the table across 187 shots 2.32 per 100 shots
- Long rally, 9+: volley to your forehand side, opponent at net hit FH through the middle ×1; FH down the line rates higher · 0.31 pts
- Rally, shots 5–8: lob to your middle, you at net hit Smash through the middle ×1; Smash crosscourt rates higher · 0.25 pts
- Return of a 2nd serve, body, ad court hit BH through the middle ×3; BH down the line rates higher · 0.19 pts
- Rally, shots 5–8: lob to your middle hit BH through the middle ×1; BH down the line rates higher · 0.18 pts