RallyIQ

WTA · Left-handed · 10 charted matches · 2022–2025

Lulu Sun

Archetype: Runs around the backhand · Forehand-dominant

Against an average opponent

Serve points won 60.1% ±3.4 raw 62.2% · tour 56.3% · 650 points
Return points won 42.5% ±3.3 raw 39.2% · tour 43.7% · 744 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 −0.04 ±0.13 better than 48% of WTA · raw −0.02
Shot selection +0.31 ±0.35 better than 79% of WTA · raw +0.33
Execution −0.39 ±1.24 better than 39% of WTA · raw −0.22
Tactical adaptability −0.05 first serves toward what's working, set to set · 10 matches
Adaptation speed −0.01 same, every two to three service games · per 100 first serves
Points left on the table 2.91 per 100 shots vs best direction · lower than 16% of WTA

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 3,120 shots.

Shot expected value

The share of points Lulu Sun 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 · 175 shots

OptionUsedWin %Tour
FH crosscourt 24% 57.3%±10.3 52.7%
FH through the middle 23% 41.2%±10.4 45.8%
FH down the line 19% 49.9%±11.3 52.2%
BH crosscourt 18% 53.3%±11.5 50.9%
BH through the middle 12% 39.6%±12.6 46.2%

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

position worth 45% to the average player · 153 shots

OptionUsedWin %Tour
BH crosscourt 48% 48.4%±8.5 47.6%
BH through the middle 25% 36.7%±10.3 43.3%
BH slice crosscourt 10% 40.2%±13.6 40.4%
BH down the line 9% 51.0%±14.1 46.8%

Return +1: drive to your middle

position worth 50% to the average player · 114 shots

OptionUsedWin %Tour
FH down the line 28% 55.0%±11.3 53.0%
FH through the middle 20% 51.9%±12.5 46.5%
BH through the middle 17% 44.2%±13.1 46.2%
FH crosscourt 15% 44.5%±13.4 52.3%
BH crosscourt 15% 43.7%±13.4 50.8%

Return +1: drive to your backhand side

position worth 44% to the average player · 102 shots

OptionUsedWin %Tour
BH crosscourt 41% 46.1%±10.4 47.8%
BH through the middle 27% 36.7%±11.4 43.0%
BH down the line 11% 42.7%±14.6 46.2%

Serve under pressure

Pressure predictability index −3 How much less varied Lulu Sun's first-serve direction gets on break points. Positive means easier to read. Based on 47 break-point first serves.

Deuce court

1st serveUsageBreak ptWon when in
Wide 30% 36% 67% / 66%
Body 25% 18% 53% / 57%
T 45% 45% 69% / 68%

328 normal · 11 break-point 1st serves

Ad court

1st serveUsageBreak ptWon when in
Wide 42% 36% 73% / 66%
Body 15% 22% 62% / 56%
T 42% 42% 84% / 64%

273 normal · 36 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 wonOptimal
Wide30% 58.2%±7.0 n=103 45% ▲
Body24% 53.1%±7.7 n=83 9% ▼
T45% 58.3%±6.0 n=153 46%

Consistent with an optimal mix (p = 0.54).
Optimal mix: +0.7 per 100 first serves.

Ad court

1st serveUsagePoints wonOptimal
Wide42% 64.9%±6.2 n=129 41%
Body16% 63.3%±8.9 n=49 1% ▼
T42% 72.5%±5.8 n=131 58% ▲

Consistent with an optimal mix (p = 0.12).
Optimal mix: +1.2 per 100 first serves.

Exploitability 0.96 points per 100 first serves What the optimal mix would win over the current one, both courts. More exploitable than 100% of WTA servers. Tested on matches they weren't fitted on, WTA mixes picked this way win 0.42 per 100 first serves on average.

Repeating the previous direction to the same court: −0.7±9.9 points per 100 against switching. Negative means returners read repeats. Tour-wide, repeating costs women about 0.4 points per 100 and costs men nothing, so men's returners don't measurably anticipate direction. (170 repeats, 458 switches.)

Return by serve direction

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

ServeCourtDirectionPointsWonvs tour
1stAd courtBody 53 42% −1.5±8.9
1stAd courtT 103 35% −0.4±6.8
1stAd courtWide 78 29% −5.4±7.2
1stDeuce courtBody 57 47% +4.3±8.8
1stDeuce courtT 51 29% −2.9±8.3
1stDeuce courtWide 136 30% −4.4±5.8
2ndAd courtBody 63 45% −10.4±8.5
2ndAd courtT 37 57% +2.4±9.9
2ndAd courtWide 27 56% +2.7±10.8
2ndDeuce courtBody 46 54% −0.1±9.4
2ndDeuce courtT 11 51% −5.3±12.8
2ndDeuce courtWide 75 51% −3.2±8.0

Signature patterns

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

Serve → +1

  1. Wide serve (ad court) → FH down the line used 6.8% · won 67% · −3.6±9.9 vs own baseline
  2. T serve (deuce court) → FH down the line used 8.7% · won 66% · −4.1±9.3 vs own baseline

Return

  1. vs wide serve (deuce court) → BH through the middle, deep used 8.9% · won 50% · +10.2±10.7 vs own baseline
  2. vs T serve (ad court) → BH through the middle, deep used 7.0% · won 44% · +4.4±11.4 vs own baseline
  3. vs wide serve (deuce court) → BH crosscourt, mid used 8.2% · won 41% · +1.3±10.8 vs own baseline
  4. vs T serve (ad court) → BH through the middle, mid used 8.2% · won 37% · −2.3±10.7 vs own baseline
  5. vs wide serve (deuce court) → BH through the middle, mid used 6.6% · won 35% · −4.5±11.2 vs own baseline

Rally, consecutive own shots

  1. BH crosscourt → BH crosscourt used 8.0% · won 53% · +5.9±10.9 vs own baseline
  2. FH through the middle → BH crosscourt used 6.8% · won 49% · +2.4±11.4 vs own baseline
  3. BH crosscourt → FH crosscourt used 7.7% · won 46% · −0.3±11.0 vs own baseline
  4. FH crosscourt → FH crosscourt used 8.0% · won 44% · −2.8±10.8 vs own baseline
  5. BH through the middle → FH crosscourt used 6.3% · won 41% · −5.5±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 Lulu Sun wins the point once the sequence happens, weighted by how often it happens. Think of them as chess openings.

  1. T serve → BH through the middle return, mid → FH down the line used 1.4% · won 56% · +8.0±12.5 vs own baseline · +12.1 vs tour on the same sequence
  2. FH down the line → FH crosscourt → BH crosscourt used 1.3% · won 53% · +5.8±12.9 vs own baseline · +14.1 vs tour on the same sequence Disrupted by Emma Raducanu (7/10)
  3. FH through the middle → FH crosscourt → BH crosscourt used 1.2% · won 52% · +4.7±13.0 vs own baseline · +13.5 vs tour on the same sequence Disrupted by Emma Raducanu (3/6)
  4. BH crosscourt → FH crosscourt → BH crosscourt used 1.9% · won 51% · +3.3±11.8 vs own baseline · +6.0 vs tour on the same sequence Disrupted by Emma Raducanu (3/9)
  5. FH crosscourt → BH crosscourt → FH crosscourt used 1.5% · won 45% · −2.3±12.4 vs own baseline · −6.2 vs tour on the same sequence
  6. BH crosscourt → FH down the line → FH crosscourt used 1.3% · won 44% · −3.9±12.8 vs own baseline · −11.7 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

T 1st serve · ad court+2.1131
FH to their backhand · rally+2.0179
Wide 1st serve · ad court+1.8129
T 1st serve · deuce court−0.2153
BH to the middle · return−0.8194

Most exposed to

Wide 1st serve · ad court−1.6136
FH to their backhand · rally−1.1147
FH to their backhand · serve +1−1.1122
Wide 1st serve · deuce court−0.4192
T 1st serve · ad court−0.4155

Active players who are best at the shot in the top weakness: Taylor Townsend, Rebecca Marino, Caroline Dolehide, Petra Kvitova, Serena Williams

Tactical fingerprint

Each bar shows how far a style trait is from the WTA average, in standard deviations.

Forehand share59%
Point-ending shots29.7%
T serves · deuce45%
Run-around forehands14%
Deep returns38%
Unforced errors / shot11.8%
T serves · ad42%
Drop shots / shot1.7%
FH down the line30%
Wide serves · ad42%
Backhand slice16%
Through the middle29%
Serve & volley0%
Chipped returns9%
Points at net5%
BH down the line16%
1st serve in58%
Avg rally length3.4
Wide serves · deuce30%

Plays most like

  1. Caroline Garcia 2013–2025 plan v
  2. Robin Montgomery 2022–2026 plan v
  3. Jule Niemeier 2021–2025 plan v
  4. Alexandra Eala 2021–2026 plan v
  5. Marta Kostyuk 2018–2026 plan v
  6. Xin Yu Wang 2019–2026 plan v
  7. Arianne Hartono 2021–2025 plan v
  8. Diana Shnaider 2022–2026 plan v

Closest from another era

  1. Daniela Hantuchova 2002–2015
  2. Jelena Dokic 2000–2009
  3. Lindsay Davenport 1995–2006

Charted matches