RallyIQ

WTA · Right-handed · 2 charted matches · 2020–2021

Ulrikke Eikeri

Shot expected value

The share of points Ulrikke Eikeri 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 · 46 shots

OptionUsedWin %Tour
BH crosscourt 41% 39.8%±12.9 47.6%
BH through the middle 37% 53.1%±13.5 43.3%

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

position worth 43% to the average player · 40 shots

OptionUsedWin %Tour
FH crosscourt 48% 36.8%±12.7 46.7%
FH through the middle 35% 39.0%±13.8 41.3%

Serve under pressure

Deuce court

1st serveUsageBreak ptWon when in
Wide 25% 40% ▲ 61% / 66%
Body 18% 20% 55% / 57%
T 57% 40% ▼ 69% / 68%

60 normal · 5 break-point 1st serves

Ad court

1st serveUsageBreak ptWon when in
Wide 57% 59% 59% / 66%
Body 17% 18% 58% / 56%
T 26% 24% 62% / 64%

46 normal · 17 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
Wide26% 39.3%±11.7 n=17
Body18% 49.4%±12.7 n=12
T55% 56.2%±10.0 n=36

Off equilibrium (p = 0.021): serve T more. Gap 5.7 points per 100 first serves.

Ad court

1st serveUsagePoints won
Wide57% 40.6%±9.9 n=36
Body17% 41.1%±12.6 n=11
T25% 47.6%±12.1 n=16

Consistent with an optimal mix (p = 0.44).

Return by serve direction

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

ServeCourtDirectionPointsWonvs tour
1stAd courtBody 10 43% −1.0±12.9
1stAd courtT 5 33% −2.2±13.1
1stAd courtWide 16 31% −3.3±11.2
1stDeuce courtBody 8 42% −1.1±13.1
1stDeuce courtT 17 29% −3.1±10.9
1stDeuce courtWide 7 41% +7.1±13.3
2ndAd courtBody 11 55% −0.1±12.8
2ndAd courtT 1 56% +1.5±14.6
2ndAd courtWide 9 49% −4.7±13.2
2ndDeuce courtBody 9 52% −2.3±13.2
2ndDeuce courtT 9 51% −5.2±13.2
2ndDeuce courtWide 6 50% −3.4±13.7

Charted matches