St Petersburg · R16 · Hard · 31 Jan 2019
Aryna Sabalenka v Alison Van Uytvanck
58–45 in points · Aryna Sabalenka won
Why it went the way it did
Aryna Sabalenka won 4.5 more points than Alison Van Uytvanck relative to what the serve alone predicted. Alison Van Uytvanck's biggest leaks: return execution −2.4, slice shot selection −2.0, return shot selection −1.7.
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 | Aryna Sabalenka | Alison Van Uytvanck | ||||||
|---|---|---|---|---|---|---|---|---|
| Dir | Sel | Exec | Total | Dir | Sel | Exec | Total | |
| Serve 1st | +0.2 | ±0.0 | −0.3 | ±0.0 | +0.1 | ±0.0 | +0.4 | +0.5 |
| Serve 2nd | +0.1 | ±0.0 | +1.2 | +1.2 | ±0.0 | ±0.0 | +0.6 | +0.5 |
| Return | −0.2 | −0.5 | +1.9 | +1.3 | +0.2 | −1.7 | −2.4 | −3.8 |
| Forehand | +0.1 | +1.2 | −1.9 | −0.7 | −0.1 | +0.7 | −1.6 | −1.1 |
| Backhand | −0.1 | +0.8 | −1.0 | −0.3 | ±0.0 | +0.6 | +0.1 | +0.7 |
| Slice | ±0.0 | −1.5 | +0.5 | −1.0 | −0.1 | −2.0 | +0.2 | −1.8 |
| Net | +0.4 | +0.1 | +1.0 | +1.4 | +0.1 | +0.2 | +0.8 | +1.2 |
| Touch | ±0.0 | +0.1 | +0.4 | +0.6 | +0.1 | −0.4 | +2.1 | +1.8 |
| All shots | +0.5 | +0.2 | +1.8 | +2.5 | +0.4 | −2.6 | +0.3 | −2.0 |
Set by set
| Set | Aryna Sabalenka | Alison Van Uytvanck | Net, Aryna | |
|---|---|---|---|---|
| 1 | +2.8 | −2.2 | +5.1 | |
| 2 | −0.3 | +0.3 | −0.6 |
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.
Aryna Sabalenka serving
| Set | Wide | Body | T |
|---|---|---|---|
| 1 | 48% 80% | 29% 67% | 24% 60% |
| 2 | 59% 61% | 3% 100% | 38% 47% |
Within sets −1.21 per 100 first serves, every two to three service games
Alison Van Uytvanck serving
| Set | Wide | Body | T |
|---|---|---|---|
| 1 | 57% 50% | 7% 100% | 36% 40% |
| 2 | 41% 44% | 18% 50% | 41% 78% |
Within sets +0.41 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.
Aryna Sabalenka
3.9 points left on the table across 156 shots 2.52 per 100 shots
- Rally, shots 5–8: drive to your forehand side hit FH through the middle ×4; FH crosscourt rates higher · 0.22 pts
- Rally, shots 5–8: drive to your middle hit FH through the middle ×3; FH crosscourt rates higher · 0.21 pts
- Serve +1: mid-depth return to your backhand side hit BH through the middle ×3; BH down the line rates higher · 0.21 pts
- Rally, shots 5–8: slice to your backhand side, opponent at net hit BH through the middle ×1; BH crosscourt rates higher · 0.20 pts
Alison Van Uytvanck
4.1 points left on the table across 168 shots 2.45 per 100 shots
- Return +1: drive to your backhand side, opponent at net hit BH through the middle ×2; BH crosscourt rates higher · 0.22 pts
- Rally, shots 5–8: drive to your forehand side hit FH through the middle ×4; FH crosscourt rates higher · 0.22 pts
- Return of a 1st serve, T, deuce court hit BH slice down the line ×2; BH slice crosscourt rates higher · 0.19 pts
- Rally, shots 5–8: drive to your backhand side hit BH slice through the middle ×3; BH slice crosscourt rates higher · 0.18 pts