Olympics · SF · Hard · 29 Sep 1988
Steffi Graf v Zina Garrison
53–24 in points · Steffi Graf won
Why it went the way it did
Steffi Graf won 14.2 more points than Zina Garrison relative to what the serve alone predicted. Zina Garrison's biggest leaks: net execution −3.2, slice shot selection −1.7, serve 2nd execution −1.6.
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 | Steffi Graf | Zina Garrison | ||||||
|---|---|---|---|---|---|---|---|---|
| Dir | Sel | Exec | Total | Dir | Sel | Exec | Total | |
| Serve 1st | −0.1 | −0.1 | −0.3 | −0.5 | −1.2 | +0.4 | −0.4 | −1.3 |
| Serve 2nd | +0.1 | −0.1 | +0.2 | +0.2 | ±0.0 | ±0.0 | −1.6 | −1.7 |
| Return | +0.6 | +0.2 | +1.8 | +2.6 | +0.8 | −0.6 | −0.1 | ±0.0 |
| Forehand | +0.3 | +0.4 | +0.1 | +0.8 | +0.1 | +0.4 | −1.0 | −0.4 |
| Backhand | +0.1 | +0.1 | +1.5 | +1.7 | +0.1 | ±0.0 | −1.0 | −0.9 |
| Slice | +0.2 | −3.0 | +2.8 | ±0.0 | +0.5 | −1.7 | −1.6 | −2.9 |
| Net | −0.3 | −0.1 | +0.4 | +0.1 | +0.2 | +0.2 | −3.2 | −2.9 |
| Touch | ±0.0 | −0.2 | −0.4 | −0.6 | +0.1 | +0.1 | ±0.0 | +0.2 |
| All shots | +0.8 | −2.7 | +6.2 | +4.3 | +0.6 | −1.4 | −9.0 | −9.8 |
Set by set
| Set | Steffi Graf | Zina Garrison | Net, Steffi | |
|---|---|---|---|---|
| 1 | +0.8 | −6.2 | +7.0 | |
| 2 | +3.5 | −3.6 | +7.2 |
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.
Steffi Graf serving
| Set | Wide | Body | T |
|---|---|---|---|
| 1 | 53% 70% | 32% 67% | 16% 100% |
| 2 | 62% 69% | 29% 67% | 10% 50% |
Within sets +0.94 per 100 first serves, every two to three service games
Zina Garrison serving
| Set | Wide | Body | T |
|---|---|---|---|
| 1 | 22% 25% | 61% 36% | 17% 33% |
| 2 | 31% 20% | 50% 13% | 19% 67% |
Within sets +0.57 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.
Steffi Graf
3.1 points left on the table across 133 shots 2.31 per 100 shots
- Rally, shots 5–8: slice to your forehand side, you at net hit FH volley through the middle ×1; FH volley crosscourt rates higher · 0.34 pts
- Return of a 1st serve, wide, ad court, server rushing the net hit BH down the line ×2; BH crosscourt rates higher · 0.23 pts
- Return of a 1st serve, wide, ad court, server rushing the net hit BH through the middle ×1; BH crosscourt rates higher · 0.15 pts
- Long rally, 9+: slice to your backhand side hit BH slice down the line ×6; BH slice through the middle rates higher · 0.15 pts
Zina Garrison
2.7 points left on the table across 138 shots 1.97 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
- Serve +1: mid-depth return to your middle, you at net hit BH volley through the middle ×1; BH volley crosscourt rates higher · 0.21 pts
- Serve +1: mid-depth return to your forehand side, you at net hit FH volley through the middle ×1; FH volley crosscourt rates higher · 0.16 pts
- Return +1: drive to your backhand side hit BH slice through the middle ×2; BH slice crosscourt rates higher · 0.13 pts