US Open · R16 · Hard · 5 Sep 2021
Leylah Fernandez v Angelique Kerber
102–91 in points · Leylah Fernandez won
Why it went the way it did
Leylah Fernandez won 4.8 more points than Angelique Kerber relative to what the serve alone predicted. Angelique Kerber's biggest leaks: slice shot selection −2.1, touch shot selection −2.1, slice execution −0.6.
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 | Leylah Fernandez | Angelique Kerber | ||||||
|---|---|---|---|---|---|---|---|---|
| Dir | Sel | Exec | Total | Dir | Sel | Exec | Total | |
| Serve 1st | ±0.0 | ±0.0 | −0.5 | −0.6 | −0.3 | ±0.0 | −0.5 | −0.7 |
| Serve 2nd | −0.1 | ±0.0 | −0.6 | −0.7 | ±0.0 | ±0.0 | +2.0 | +1.9 |
| Return | −0.5 | −0.4 | +6.4 | +5.5 | +0.3 | ±0.0 | +2.5 | +2.9 |
| Forehand | −0.9 | +3.1 | +11.9 | +14.0 | +0.5 | +2.4 | +5.7 | +8.5 |
| Backhand | −0.2 | +0.5 | −1.8 | −1.5 | −0.5 | +0.3 | +2.8 | +2.6 |
| Slice | −0.5 | −3.2 | −0.3 | −4.0 | +0.1 | −2.1 | −0.6 | −2.6 |
| Net | −0.4 | +1.1 | +1.8 | +2.6 | −0.3 | +0.3 | +0.2 | +0.2 |
| Touch | −0.1 | +0.3 | −0.6 | −0.4 | −0.3 | −2.1 | −0.2 | −2.7 |
| All shots | −2.7 | +1.3 | +16.3 | +14.9 | −0.5 | −1.3 | +11.8 | +10.1 |
Set by set
| Set | Leylah Fernandez | Angelique Kerber | Net, Leylah | |
|---|---|---|---|---|
| 1 | +2.2 | +5.2 | −3.0 | |
| 2 | +8.5 | +5.1 | +3.4 | |
| 3 | +4.2 | −0.3 | +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.
Leylah Fernandez serving
| Set | Wide | Body | T |
|---|---|---|---|
| 1 | 42% 53% | 19% 29% | 39% 50% |
| 2 | 29% 80% | 26% 56% | 46% 69% |
| 3 | 37% 55% | 7% 50% | 57% 76% |
Set to set −0.03 per 100 first serves in sets 2+
Within sets +0.15 per 100 first serves, every two to three service games
Angelique Kerber serving
| Set | Wide | Body | T |
|---|---|---|---|
| 1 | 45% 62% | 28% 50% | 28% 50% |
| 2 | 66% 56% | 22% 56% | 12% 80% |
| 3 | 50% 55% | 36% 50% | 14% 33% |
Set to set −1.66 per 100 first serves in sets 2+
Within sets +0.14 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.
Leylah Fernandez
15.3 points left on the table across 444 shots 3.45 per 100 shots
- Return of a 1st serve, wide, ad court hit FH through the middle ×11; FH inside-out rates higher · 1.03 pts
- Return of a 1st serve, wide, ad court hit FH down the line ×5; FH inside-out rates higher · 0.87 pts
- Rally, shots 5–8: drive to your middle hit FH through the middle ×11; FH crosscourt rates higher · 0.77 pts
- Serve +1: deep return to your middle hit FH through the middle ×10; FH crosscourt rates higher · 0.61 pts
Angelique Kerber
13.1 points left on the table across 433 shots 3.03 per 100 shots
- Return of a 1st serve, T, deuce court hit FH through the middle ×19; FH inside-in rates higher · 1.19 pts
- Serve +1: mid-depth return to your middle hit BH through the middle ×10; BH crosscourt rates higher · 0.61 pts
- Return of a 1st serve, wide, ad court hit FH through the middle ×6; FH inside-out rates higher · 0.56 pts
- Return +1: drive to your middle hit FH through the middle ×8; FH down the line rates higher · 0.52 pts