RallyIQ

WTA · Right-handed · 5 charted matches · 2022–2025

Katherine Sebov

Shot expected value

The share of points Katherine Sebov 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 middle

position worth 50% to the average player · 68 shots

OptionUsedWin %Tour
BH through the middle 26% 40.1%±13.1 46.2%
FH through the middle 21% 35.7%±13.5 45.8%
FH crosscourt 16% 46.9%±14.7 52.7%

Rally, shots 5–8: drive to your forehand side

position worth 43% to the average player · 57 shots

OptionUsedWin %Tour
FH through the middle 40% 44.8%±12.5 41.3%
FH crosscourt 30% 44.2%±13.4 46.7%
FH down the line 18% 33.3%±14.1 44.9%

Rally, shots 5–8: drive to your backhand side

position worth 45% to the average player · 56 shots

OptionUsedWin %Tour
BH through the middle 54% 41.3%±11.5 43.3%
BH crosscourt 23% 47.0%±14.3 47.6%
BH down the line 23% 46.5%±14.3 46.8%

Serve +1: mid-depth return to your middle

position worth 51% to the average player · 43 shots

OptionUsedWin %Tour
BH through the middle 40% 35.9%±13.0 46.3%
FH down the line 33% 54.9%±14.0 53.3%

Serve under pressure

Pressure predictability index +3 How much less varied Katherine Sebov's first-serve direction gets on break points. Positive means easier to read. Based on 42 break-point first serves.

Deuce court

1st serveUsageBreak ptWon when in
Wide 41% 33% 61% / 66%
Body 46% 58% ▲ 49% / 57%
T 14% 8% 63% / 68%

123 normal · 12 break-point 1st serves

Ad court

1st serveUsageBreak ptWon when in
Wide 30% 27% 60% / 66%
Body 41% 40% 55% / 56%
T 29% 33% 60% / 64%

94 normal · 30 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 serveUsagePoints won
Wide40% 46.7%±9.0 n=54
Body47% 38.9%±8.3 n=63
T13% 51.3%±11.9 n=18

Consistent with an optimal mix (p = 0.10).

Ad court

1st serveUsagePoints won
Wide29% 46.8%±10.1 n=36
Body41% 50.9%±9.1 n=51
T30% 47.0%±10.0 n=37

Consistent with an optimal mix (p = 0.75).

Return by serve direction

Return points won against each serve direction, compared with the tour average.

ServeCourtDirectionPointsWonvs tour
1stAd courtBody 20 32% −11.6±10.9
1stAd courtT 18 33% −2.9±11.1
1stAd courtWide 22 37% +2.7±11.0
1stDeuce courtBody 20 38% −5.0±11.3
1stDeuce courtT 26 28% −4.2±9.9
1stDeuce courtWide 26 24% −10.4±9.3
2ndAd courtBody 19 48% −7.1±11.7
2ndAd courtT 4 52% −3.5±14.1
2ndAd courtWide 15 51% −2.3±12.3
2ndDeuce courtBody 23 42% −12.3±11.2
2ndDeuce courtT 14 45% −11.0±12.3
2ndDeuce courtWide 5 49% −4.8±13.9

Charted matches