Madrid · R64 · Clay · 29 Apr 2021
Iga Swiatek v Alison Riske Amritraj
61–41 in points · Iga Swiatek won
Why it went the way it did
Iga Swiatek won 9.9 more points than Alison Riske Amritraj relative to what the serve alone predicted. Alison Riske Amritraj's biggest leaks: backhand execution −1.3, serve 2nd execution −1.1, slice shot selection −1.0.
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 | Iga Swiatek | Alison Riske Amritraj | ||||||
|---|---|---|---|---|---|---|---|---|
| Dir | Sel | Exec | Total | Dir | Sel | Exec | Total | |
| Serve 1st | +0.1 | ±0.0 | +1.1 | +1.2 | +0.2 | ±0.0 | +0.1 | +0.3 |
| Serve 2nd | ±0.0 | ±0.0 | −0.7 | −0.6 | −0.1 | ±0.0 | −1.1 | −1.1 |
| Return | +0.1 | ±0.0 | −1.6 | −1.5 | −0.1 | +0.2 | −0.4 | −0.3 |
| Forehand | +0.2 | +0.8 | +4.2 | +5.2 | −0.8 | +0.9 | −0.7 | −0.5 |
| Backhand | +0.6 | +0.4 | +2.6 | +3.5 | ±0.0 | +0.5 | −1.3 | −0.7 |
| Slice | ±0.0 | −0.6 | ±0.0 | −0.6 | +0.1 | −1.0 | −0.3 | −1.2 |
| Net | +0.1 | +0.1 | −0.3 | ±0.0 | +0.1 | +0.1 | +0.1 | +0.2 |
| Touch | ±0.0 | ±0.0 | −0.5 | −0.5 | ±0.0 | ±0.0 | ±0.0 | ±0.0 |
| All shots | +1.2 | +0.7 | +4.7 | +6.6 | −0.6 | +0.8 | −3.4 | −3.3 |
Set by set
| Set | Iga Swiatek | Alison Riske Amritraj | Net, Iga | |
|---|---|---|---|---|
| 1 | +1.7 | −1.9 | +3.5 | |
| 2 | +5.0 | −1.4 | +6.3 |
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.
Iga Swiatek serving
| Set | Wide | Body | T |
|---|---|---|---|
| 1 | 48% 69% | 21% 57% | 30% 60% |
| 2 | 63% 67% | 5% 0% | 32% 83% |
Set to set ±0.00 per 100 first serves in sets 2+
Within sets −1.30 per 100 first serves, every two to three service games
Alison Riske Amritraj serving
| Set | Wide | Body | T |
|---|---|---|---|
| 1 | 44% 71% | 19% 33% | 38% 33% |
| 2 | 71% 42% | 9% 67% | 21% 43% |
Within sets +1.48 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.
Iga Swiatek
2.9 points left on the table across 170 shots 1.69 per 100 shots
- Rally, shots 5–8: drive to your middle hit FH through the middle ×5; FH crosscourt rates higher · 0.35 pts
- Rally, shots 5–8: volley to your backhand side, opponent at net hit BH through the middle ×1; BH crosscourt rates higher · 0.23 pts
- Return of a 1st serve, wide, deuce court hit FH down the line ×2; FH crosscourt rates higher · 0.14 pts
- Serve +1: mid-depth return to your backhand side hit BH drop shot through the middle ×1; BH drop shot crosscourt rates higher · 0.11 pts
Alison Riske Amritraj
4.8 points left on the table across 159 shots 3.02 per 100 shots
- Serve +1: mid-depth return to your middle hit FH through the middle ×5; FH crosscourt rates higher · 0.42 pts
- Rally, shots 5–8: drive to your forehand side hit FH through the middle ×6; FH crosscourt rates higher · 0.33 pts
- Rally, shots 5–8: drive to your middle hit FH through the middle ×4; FH crosscourt rates higher · 0.28 pts
- Return of a 1st serve, T, deuce court hit FH through the middle ×1; FH inside-out rates higher · 0.22 pts