RallyIQ

WTA · Right-handed · 6 charted matches · 2014–2018

Kurumi Nara

Against an average opponent

Serve points won 53.6% ±4.0 raw 49.9% · tour 56.3% · 375 points
Return points won 43.1% ±4.0 raw 42.2% · tour 43.7% · 379 points

Serve and return points won, refitted against every opponent at once so a record built on weak or strong opposition is put on the same scale. Career, all surfaces, with a 90% margin. Raw is the plain share of points won.

Value per 100 shots

Direction choice −0.30 ±0.37 better than 7% of WTA · raw −0.27
Shot selection +0.26 ±0.28 better than 74% of WTA · raw +0.31
Execution −0.43 ±0.71 better than 37% of WTA · raw −0.06

Points gained per 100 shots compared with an average tour player in the same position, adjusted for the strength of the opponents faced, with a 90% margin (shots clustered by match). Raw is before the opponent adjustment. Built on 2,262 shots.

Shot expected value

The share of points Kurumi Nara 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 · 195 shots

OptionUsedWin %Tour
FH crosscourt 20% 51.8%±10.7 52.7%
FH through the middle 19% 53.7%±10.8 45.8%
BH through the middle 17% 46.7%±11.2 46.2%
BH crosscourt 15% 58.4%±11.5 50.9%
FH down the line 15% 44.9%±11.6 52.2%
BH down the line 12% 36.4%±11.9 50.0%

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

position worth 43% to the average player · 145 shots

OptionUsedWin %Tour
FH crosscourt 34% 46.2%±9.8 46.7%
FH through the middle 32% 39.8%±9.9 41.3%
FH down the line 30% 51.5%±10.3 44.9%

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

position worth 45% to the average player · 129 shots

OptionUsedWin %Tour
BH crosscourt 50% 46.5%±8.9 47.6%
BH through the middle 34% 41.7%±10.1 43.3%
BH down the line 16% 40.9%±12.8 46.8%

Long rally, 9+: drive to your middle

position worth 51% to the average player · 107 shots

OptionUsedWin %Tour
FH down the line 25% 63.0%±11.6 53.1%
FH through the middle 20% 42.0%±12.7 46.0%
BH through the middle 16% 49.3%±13.5 46.3%
FH crosscourt 14% 58.8%±13.7 52.8%
BH crosscourt 13% 53.4%±14.1 50.8%
BH down the line 12% 58.6%±14.1 51.7%

Serve under pressure

Pressure predictability index +2 How much less varied Kurumi Nara's first-serve direction gets on break points. Positive means easier to read. Based on 49 break-point first serves.

Deuce court

1st serveUsageBreak ptWon when in
Wide 37% 40% 56% / 66%
Body 36% 20% ▼ 55% / 57%
T 28% 40% ▲ 54% / 68%

183 normal · 10 break-point 1st serves

Ad court

1st serveUsageBreak ptWon when in
Wide 39% 38% 64% / 66%
Body 30% 23% 55% / 56%
T 31% 38% 57% / 64%

143 normal · 39 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% 48.7%±8.2 n=71
Body35% 51.2%±8.3 n=67
T29% 42.4%±8.8 n=55

Consistent with an optimal mix (p = 0.27).

Ad court

1st serveUsagePoints won
Wide39% 55.3%±8.1 n=71
Body29% 52.6%±9.1 n=52
T32% 48.3%±8.7 n=59

Consistent with an optimal mix (p = 0.48).

Return by serve direction

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

ServeCourtDirectionPointsWonvs tour
1stAd courtBody 24 39% −4.7±10.9
1stAd courtT 58 28% −7.5±7.9
1stAd courtWide 32 34% ±0.0±9.9
1stDeuce courtBody 25 45% +2.5±11.0
1stDeuce courtT 26 26% −6.0±9.7
1stDeuce courtWide 68 40% +6.0±8.1
2ndAd courtBody 44 62% +6.5±9.3
2ndAd courtT 11 55% −0.1±12.8
2ndAd courtWide 15 51% −2.3±12.3
2ndDeuce courtBody 37 51% −3.2±10.0
2ndDeuce courtT 17 55% −1.1±11.9
2ndDeuce courtWide 22 54% +0.3±11.4

Signature patterns

Recurring sequences that win more than Kurumi Nara's own baseline, ranked by edge weighted by how often they're used.

Serve → +1

  1. Body serve (deuce court) → FH through the middle used 11.0% · won 49% · −6.1±11.8 vs own baseline

Return

  1. Not enough data

Rally, consecutive own shots

  1. FH through the middle → BH crosscourt used 4.6% · won 61% · +7.7±11.0 vs own baseline
  2. FH down the line → BH crosscourt used 6.6% · won 59% · +5.9±10.1 vs own baseline
  3. FH crosscourt → FH down the line used 5.2% · won 56% · +2.7±10.8 vs own baseline
  4. BH crosscourt → FH crosscourt used 5.4% · won 55% · +1.7±10.7 vs own baseline
  5. BH through the middle → FH down the line used 4.1% · won 55% · +1.5±11.5 vs own baseline

Discovered sequences

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

  1. FH down the line → BH crosscourt → BH crosscourt used 1.7% · won 55% · +5.1±11.8 vs own baseline · +12.5 vs tour on the same sequence Disrupted by Agnieszka Radwanska (3/6), Johanna Larsson (7/8)
  2. FH crosscourt → FH crosscourt → FH down the line used 1.5% · won 55% · +4.3±12.2 vs own baseline · +12.3 vs tour on the same sequence Disrupted by Johanna Larsson (6/6)
  3. BH crosscourt → BH crosscourt → BH through the middle used 1.2% · won 55% · +4.8±12.8 vs own baseline · +18.6 vs tour on the same sequence Disrupted by Agnieszka Radwanska (3/6)
  4. FH through the middle → FH crosscourt → FH crosscourt used 1.1% · won 51% · +1.2±13.0 vs own baseline · +6.6 vs tour on the same sequence
  5. BH through the middle → FH crosscourt → FH through the middle used 1.1% · won 51% · +1.2±13.0 vs own baseline · +14.3 vs tour on the same sequence Disrupted by Johanna Larsson (5/7)
  6. BH through the middle → FH crosscourt → FH crosscourt used 1.2% · won 50% · −0.1±12.9 vs own baseline · +5.5 vs tour on the same sequence

Strengths and vulnerabilities

Value per 100 shots compared with the average player hitting (strengths) or facing (vulnerabilities) the same shot. Only shot types seen at least 120 times.

Hurts opponents most with

BH to their backhand · rally+1.2159
FH to the middle · rally+1.0134
FH to their forehand · rally±0.0160
BH to the middle · rally−1.2120
FH to their backhand · rally−2.3144

Most exposed to

BH to the middle · rally−1.4139
FH to their forehand · rally−0.1215
FH to the middle · rally+0.2130
BH to their backhand · rally+0.4133

Active players who are best at the shot in the top weakness: Darja Vidmanova, Caroline Wozniacki, Katie Volynets, Anna Karolina Schmiedlova, Marie Bouzkova

Charted matches