RallyIQ

WTA · Right-handed · 9 charted matches · 2014–2020

Saisai Zheng

Archetype: Rarely serves the T · Patient builder

Against an average opponent

Serve points won 56.9% ±3.8 raw 56.7% · tour 56.3% · 601 points
Return points won 44.7% ±3.8 raw 41.8% · tour 43.7% · 662 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 −0.36 ±0.16 better than 3% of WTA · raw −0.36
Shot selection −0.40 ±0.15 better than 17% of WTA · raw −0.39
Execution −0.20 ±0.75 better than 48% of WTA · raw −0.16
Points left on the table 3.22 per 100 shots vs best direction · lower than 4% 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 3,810 shots.

Shot expected value

The share of points Saisai Zheng 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 · 218 shots

OptionUsedWin %Tour
BH crosscourt 36% 37.9%±8.0 47.6%
BH through the middle 28% 52.1%±9.2 43.3%
BH slice crosscourt 15% 46.3%±11.4 40.4%
BH slice through the middle 9% 42.2%±12.8 34.4%
BH down the line 9% 50.9%±13.0 46.8%

Rally, shots 5–8: drive to your middle

position worth 50% to the average player · 215 shots

OptionUsedWin %Tour
FH down the line 26% 50.6%±9.4 52.2%
FH through the middle 20% 47.1%±10.3 45.8%
FH crosscourt 14% 61.1%±11.3 52.7%
BH through the middle 10% 49.4%±12.8 46.2%
BH crosscourt 9% 49.2%±13.2 50.9%
BH slice through the middle 7% 54.2%±13.9 44.8%
FH down the line + approach 6% 71.9%±12.9 68.6%

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

position worth 43% to the average player · 202 shots

OptionUsedWin %Tour
FH through the middle 42% 56.0%±8.0 41.3%
FH crosscourt 25% 43.4%±9.7 46.7%
FH down the line 24% 45.6%±9.9 44.9%
FH slice through the middle 6% 27.6%±13.0 29.2%

Long rally, 9+: drive to your forehand side

position worth 44% to the average player · 129 shots

OptionUsedWin %Tour
FH through the middle 35% 42.0%±10.1 41.5%
FH crosscourt 34% 47.5%±10.3 47.0%
FH down the line 26% 49.6%±11.3 46.4%

Serve under pressure

Pressure predictability index +3 How much less varied Saisai Zheng's first-serve direction gets on break points. Positive means easier to read. Based on 70 break-point first serves.

Deuce court

1st serveUsageBreak ptWon when in
Wide 43% 45% 62% / 66%
Body 24% 9% ▼ 63% / 57%
T 33% 45% ▲ 67% / 68%

291 normal · 22 break-point 1st serves

Ad court

1st serveUsageBreak ptWon when in
Wide 50% 42% ▼ 58% / 66%
Body 18% 19% 59% / 56%
T 32% 40% 66% / 64%

240 normal · 48 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
Wide43% 59.3%±6.3 n=135 58% ▲
Body23% 57.5%±8.0 n=73 8% ▼
T34% 60.1%±6.9 n=105 34%

Consistent with an optimal mix (p = 0.89).
Optimal mix: +0.6 per 100 first serves.

Ad court

1st serveUsagePoints wonOptimal
Wide49% 52.4%±6.3 n=140 49%
Body18% 55.9%±9.0 n=53 3% ▼
T33% 55.5%±7.3 n=95 48% ▲

Consistent with an optimal mix (p = 0.75).
Optimal mix: +0.5 per 100 first serves.

Exploitability 0.54 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: −7.4±9.0 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. (220 repeats, 363 switches.)

Return by serve direction

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

ServeCourtDirectionPointsWonvs tour
1stAd courtBody 25 37% −7.2±10.7
1stAd courtT 83 35% −0.4±7.4
1stAd courtWide 87 35% +0.9±7.3
1stDeuce courtBody 35 49% +6.3±10.2
1stDeuce courtT 73 32% −0.4±7.5
1stDeuce courtWide 103 35% +1.5±6.8
2ndAd courtBody 45 54% −1.0±9.5
2ndAd courtT 22 61% +5.6±11.1
2ndAd courtWide 54 45% −8.2±8.9
2ndDeuce courtBody 59 55% +1.0±8.7
2ndDeuce courtT 44 51% −4.9±9.6
2ndDeuce courtWide 30 52% −1.9±10.6

Signature patterns

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

Serve → +1

  1. T serve (deuce court) → FH down the line used 5.8% · won 58% · −3.9±11.5 vs own baseline
  2. Body serve (deuce court) → FH through the middle used 6.3% · won 58% · −4.2±11.2 vs own baseline
  3. Body serve (deuce court) → FH down the line used 6.3% · won 52% · −9.8±11.3 vs own baseline
  4. Wide serve (deuce court) → FH down the line used 6.9% · won 50% · −11.7±11.1 vs own baseline

Return

  1. vs wide serve (deuce court) → FH through the middle, mid used 10.2% · won 50% · +5.0±11.1 vs own baseline
  2. vs wide serve (ad court) → BH crosscourt, mid used 8.2% · won 47% · +2.0±11.8 vs own baseline
  3. vs wide serve (deuce court) → FH through the middle, deep used 9.0% · won 43% · −1.8±11.4 vs own baseline

Rally, consecutive own shots

  1. FH crosscourt → FH crosscourt used 4.0% · won 54% · +4.4±10.9 vs own baseline
  2. BH through the middle → FH through the middle used 5.5% · won 52% · +2.3±10.0 vs own baseline
  3. FH through the middle → FH crosscourt used 3.4% · won 53% · +2.9±11.3 vs own baseline
  4. FH through the middle → FH down the line used 3.1% · won 53% · +3.0±11.6 vs own baseline
  5. FH through the middle → FH through the middle used 4.4% · won 52% · +1.7±10.6 vs own baseline

Discovered sequences

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

  1. BH through the middle → FH crosscourt → FH through the middle used 1.3% · won 55% · +3.3±11.5 vs own baseline · +18.6 vs tour on the same sequence Disrupted by Ashleigh Barty (3/6), Kiki Bertens (4/6)
  2. FH crosscourt → FH crosscourt → FH crosscourt used 1.2% · won 54% · +2.6±11.8 vs own baseline · +8.3 vs tour on the same sequence Disrupted by Kiki Bertens (5/13)
  3. BH crosscourt → BH crosscourt → BH crosscourt used 0.8% · won 53% · +2.0±12.8 vs own baseline · +7.6 vs tour on the same sequence Disrupted by Kiki Bertens (6/8)
  4. FH through the middle → FH crosscourt → FH through the middle used 1.3% · won 52% · +0.4±11.6 vs own baseline · +10.8 vs tour on the same sequence Disrupted by Kiki Bertens (9/14)
  5. FH down the line → BH crosscourt → BH through the middle used 0.8% · won 49% · −1.7±13.0 vs own baseline · +2.8 vs tour on the same sequence
  6. FH through the middle → FH crosscourt → FH down the line used 0.8% · won 49% · −1.7±13.0 vs own baseline · +5.3 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

FH to the middle · return+1.5132
BH to the middle · rally+1.3151
FH to the middle · rally+1.3215
BH to their backhand · rally+1.1186
BH to the middle · return+0.2130

Most exposed to

FH to their forehand · serve +1−2.0130
BH to the middle · return−1.5141
Wide 1st serve · deuce court+0.2155
BH to the middle · rally+0.2174
T 1st serve · ad court+0.5126

Active players who are best at the shot in the top weakness: Barbora Krejcikova, Shelby Rogers, Sara Sorribes Tormo, Jil Teichmann, Maria Sakkari

Tactical fingerprint

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

FH down the line37%
Through the middle37%
Avg rally length5.0
Points at net14%
Backhand slice31%
Wide serves · ad49%
Chipped returns17%
Wide serves · deuce43%
1st serve in63%
Serve & volley2%
Drop shots / shot1.6%
Forehand share54%
Deep returns32%
Run-around forehands4%
T serves · deuce34%
T serves · ad33%
BH down the line17%
Unforced errors / shot8.5%
Point-ending shots17.5%

Plays most like

  1. Alize Cornet 2013–2024 plan v
  2. Agnieszka Radwanska 2007–2018 plan v
  3. Marie Bouzkova 2018–2026 plan v
  4. Viktorija Golubic 2017–2026 plan v
  5. Alina Korneeva 2023–2026 plan v
  6. Emma Navarro 2019–2026 plan v
  7. Yafan Wang 2019–2025 plan v
  8. Coco Gauff 2019–2026 plan v

Closest from another era

  1. Martina Hingis 1996–2007
  2. Arantxa Sanchez Vicario 1988–2001
  3. Jennifer Capriati 1990–2002

Charted matches