RallyIQ

WTA · Right-handed · 3 charted matches · 1990–1993

Mary Joe Fernandez

Shot expected value

The share of points Mary Joe Fernandez 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 forehand side

position worth 43% to the average player · 68 shots

OptionUsedWin %Tour
FH through the middle 51% 38.7%±10.8 41.3%
FH down the line 25% 37.8%±13.1 44.9%
FH crosscourt 24% 51.0%±13.7 46.7%

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

position worth 53% to the average player · 68 shots

OptionUsedWin %Tour
BH crosscourt 51% 48.3%±11.1 52.9%
FH inside-out 16% 52.8%±14.8 56.8%
BH through the middle 15% 59.9%±14.7 44.8%

Return +1: drive to your forehand side

position worth 43% to the average player · 41 shots

OptionUsedWin %Tour
FH crosscourt 41% 50.1%±13.5 47.6%
FH through the middle 41% 43.9%±13.4 41.3%

Long rally, 9+: slice to your backhand side

position worth 53% to the average player · 39 shots

OptionUsedWin %Tour
BH crosscourt 51% 54.0%±13.0 53.0%
BH through the middle 33% 56.0%±14.2 47.3%

Serve under pressure

Deuce court

1st serveUsageBreak ptWon when in
Wide 37% 33% 56% / 66%
Body 10% 17% 58% / 57%
T 53% 50% 61% / 68%

109 normal · 6 break-point 1st serves

Ad court

1st serveUsageBreak ptWon when in
Wide 69% 70% 58% / 66%
Body 3% 0% 53% / 56%
T 29% 30% 64% / 64%

80 normal · 27 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
Wide37% 44.2%±9.6 n=42
Body10% 50.4%±12.7 n=12
T53% 51.5%±8.6 n=61

Consistent with an optimal mix (p = 0.42).

Ad court

1st serveUsagePoints won
Wide69% 52.5%±8.1 n=74
Body2% 49.0%±14.5 n=2
T29% 53.9%±10.5 n=31

Consistent with an optimal mix (p = 0.95).

Return by serve direction

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

ServeCourtDirectionPointsWonvs tour
1stAd courtBody 1 46% +1.8±14.7
1stAd courtT 25 38% +2.0±10.7
1stAd courtWide 47 34% −0.3±8.9
1stDeuce courtBody 7 43% ±0.0±13.4
1stDeuce courtT 46 36% +4.2±9.1
1stDeuce courtWide 26 33% −1.5±10.3
2ndAd courtBody 7 50% −5.0±13.5
2ndAd courtT 8 54% −1.1±13.3
2ndAd courtWide 27 51% −2.6±10.9
2ndDeuce courtBody 12 56% +1.1±12.6
2ndDeuce courtT 9 46% −10.4±13.1
2ndDeuce courtWide 20 58% +4.5±11.5

Discovered sequences

Mined from every me → opponent → me run of three shots, with no templates. Ranked by how much more often Mary Joe Fernandez wins the point once the sequence happens, weighted by how often it happens. Think of them as chess openings.

  1. BH crosscourt → BH slice crosscourt → BH crosscourt used 2.6% · won 44% · −1.9±12.7 vs own baseline · −11.5 vs tour on the same sequence Disrupted by Steffi Graf (7/17)
  2. FH down the line → BH slice crosscourt → BH crosscourt used 2.3% · won 44% · −2.2±13.0 vs own baseline · −13.1 vs tour on the same sequence Disrupted by Steffi Graf (6/15)

Charted matches