WTA · Right-handed · 2 charted matches · 2016–2019
Risa Ozaki
Shot expected value
The share of points Risa Ozaki goes on to win after each option in the positions they face most often, shrunk toward tour average when the sample is small. Showing the 8 most-used options; teal marks the best one with at least 30 shots.
Rally, shots 5–8: drive to your backhand side
position worth 45% to the average player · 66 shots
| Option | Used | Win % | Tour |
|---|---|---|---|
| BH through the middle | 53% | 44.8%±11.0 | 43.3% |
| BH crosscourt | 23% | 44.3%±13.8 | 47.6% |
Rally, shots 5–8: drive to your forehand side
position worth 43% to the average player · 55 shots
| Option | Used | Win % | Tour |
|---|---|---|---|
| FH through the middle | 36% | 40.7%±12.8 | 41.3% |
| FH crosscourt | 36% | 35.9%±12.5 | 46.7% |
| FH down the line | 27% | 45.6%±13.8 | 44.9% |
Rally, shots 5–8: drive to your middle
position worth 50% to the average player · 41 shots
| Option | Used | Win % | Tour |
|---|---|---|---|
| FH down the line | 37% | 44.1%±13.8 | 52.2% |
| FH through the middle | 32% | 48.9%±14.3 | 45.8% |
Serve under pressure
Deuce court
| 1st serve | Usage | Break pt | Won when in |
|---|---|---|---|
| Wide | 33% | 25% | 63% / 66% |
| Body | 28% | 38% ▲ | 54% / 57% |
| T | 39% | 38% | 66% / 68% |
76 normal · 8 break-point 1st serves
Ad court
| 1st serve | Usage | Break pt | Won when in |
|---|---|---|---|
| Wide | 39% | 30% ▼ | 57% / 66% |
| Body | 22% | 30% ▲ | 53% / 56% |
| T | 39% | 40% | 71% / 64% |
64 normal · 10 break-point 1st serves
Is the serve mix in equilibrium?
Game theory says a well-mixed server wins equally often with every direction they use. If one direction wins more, it's underused and points are being left behind. This is the minimax test Walker and Wooders ran on Wimbledon finals, applied to every charted first serve. Win rates include faults. "Optimal" allows for returners reading a habit. A direction loses 0.19 points per 100 serves for every 10 points of habitual usage, measured from WTA servers whose mix drifted between matches. Shifts stay within the range servers' habits actually vary, the only range that response was measured over.
Deuce court
| 1st serve | Usage | Points won |
|---|---|---|
| Wide | 32% | 47.9%±10.9 n=27 |
| Body | 29% | 48.2%±11.2 n=24 |
| T | 39% | 46.8%±10.3 n=33 |
Consistent with an optimal mix (p = 0.97).
Ad court
| 1st serve | Usage | Points won |
|---|---|---|
| Wide | 38% | 46.5%±10.8 n=28 |
| Body | 23% | 48.2%±12.0 n=17 |
| T | 39% | 62.4%±10.4 n=29 |
Off equilibrium (p = 0.027): serve T more. Gap 9.3 points per 100 first serves.
Return by serve direction
Return points won against each serve direction, compared with the tour average.
| Serve | Court | Direction | Points | Won | vs tour | |
|---|---|---|---|---|---|---|
| 1st | Ad court | Body | 12 | 53% | +8.9±12.7 | |
| 1st | Ad court | T | 12 | 33% | −3.0±11.9 | |
| 1st | Ad court | Wide | 16 | 33% | −1.1±11.4 | |
| 1st | Deuce court | Body | 11 | 43% | +0.8±12.7 | |
| 1st | Deuce court | T | 15 | 39% | +7.1±12.0 | |
| 1st | Deuce court | Wide | 33 | 34% | −0.4±9.8 | |
| 2nd | Ad court | Body | 13 | 55% | −0.4±12.5 | |
| 2nd | Ad court | T | 6 | 54% | −0.8±13.7 | |
| 2nd | Ad court | Wide | 23 | 53% | −0.6±11.3 | |
| 2nd | Deuce court | Body | 10 | 53% | −1.1±13.0 | |
| 2nd | Deuce court | T | 8 | 55% | −1.3±13.3 | |
| 2nd | Deuce court | Wide | 10 | 50% | −3.4±13.0 |