RallyIQ

WTA · Right-handed · 7 charted matches · 2021–2022

Harmony Tan

Against an average opponent

Serve points won 55.1% ±3.6 raw 51.2% · tour 56.3% · 514 points
Return points won 44.9% ±3.8 raw 43.1% · tour 43.7% · 427 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 +0.06 ±0.07 better than 66% of WTA · raw +0.06
Shot selection −0.57 ±0.60 better than 9% of WTA · raw −0.57
Execution −0.10 ±1.93 better than 57% of WTA · raw −0.08
Points left on the table 2.65 per 100 shots vs best direction · lower than 44% 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 2,962 shots.

Shot expected value

The share of points Harmony Tan 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 · 165 shots

OptionUsedWin %Tour
FH crosscourt 28% 40.2%±9.9 52.7%
FH down the line 19% 43.2%±11.3 52.2%
BH crosscourt 18% 49.4%±11.7 50.9%
BH through the middle 15% 43.7%±12.3 46.2%
FH through the middle 9% 43.3%±13.8 45.8%

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

position worth 43% to the average player · 142 shots

OptionUsedWin %Tour
FH crosscourt 37% 51.2%±9.6 46.7%
FH through the middle 25% 48.7%±11.0 41.3%
FH down the line 23% 45.2%±11.2 44.9%
FH slice through the middle 8% 33.9%±13.8 29.2%

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

position worth 45% to the average player · 113 shots

OptionUsedWin %Tour
BH crosscourt 36% 46.8%±10.5 47.6%
BH down the line 19% 42.3%±12.7 46.8%
BH through the middle 16% 46.5%±13.3 43.3%
BH slice through the middle 14% 35.8%±13.1 34.4%
BH slice crosscourt 9% 40.3%±14.7 40.4%

Long rally, 9+: drive to your forehand side

position worth 44% to the average player · 88 shots

OptionUsedWin %Tour
FH crosscourt 42% 48.1%±10.9 47.0%
FH through the middle 25% 48.3%±12.7 41.5%
FH down the line 25% 43.5%±12.6 46.4%

Serve under pressure

Pressure predictability index −4 How much less varied Harmony Tan's first-serve direction gets on break points. Positive means easier to read. Based on 77 break-point first serves.

Deuce court

1st serveUsageBreak ptWon when in
Wide 43% 38% 63% / 66%
Body 26% 46% ▲ 62% / 57%
T 31% 15% ▼ 63% / 68%

252 normal · 13 break-point 1st serves

Ad court

1st serveUsageBreak ptWon when in
Wide 35% 39% 64% / 66%
Body 17% 27% ▲ 59% / 56%
T 47% 34% ▼ 57% / 64%

184 normal · 64 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% 49.0%±6.9 n=114 41% ▼
Body27% 58.3%±8.1 n=71 22% ▼
T30% 49.2%±7.8 n=80 37% ▲

Consistent with an optimal mix (p = 0.17).
Optimal mix: ±0.0 per 100 first serves.

Ad court

1st serveUsagePoints wonOptimal
Wide36% 49.3%±7.5 n=90 51% ▲
Body20% 59.3%±9.1 n=49 20%
T44% 46.3%±7.0 n=109 29% ▼

Consistent with an optimal mix (p = 0.05).
Optimal mix: +0.2 per 100 first serves.

Exploitability 0.09 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: +11.9±4.4 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. (150 repeats, 349 switches.)

Return by serve direction

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

ServeCourtDirectionPointsWonvs tour
1stAd courtBody 49 38% −5.7±9.0
1stAd courtT 29 30% −5.6±9.8
1stAd courtWide 47 37% +2.3±9.0
1stDeuce courtBody 42 43% +0.1±9.6
1stDeuce courtT 39 34% +2.1±9.4
1stDeuce courtWide 62 39% +5.3±8.4
2ndAd courtBody 50 61% +5.6±9.0
2ndAd courtT 6 51% −3.6±13.7
2ndAd courtWide 24 50% −3.4±11.2
2ndDeuce courtBody 44 52% −2.6±9.6
2ndDeuce courtT 15 55% −0.9±12.2
2ndDeuce courtWide 20 50% −3.5±11.6

Signature patterns

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

Serve → +1

  1. Not enough data

Return

  1. Not enough data

Rally, consecutive own shots

  1. BH crosscourt → FH crosscourt used 9.2% · won 52% · +8.1±10.4 vs own baseline
  2. FH crosscourt → BH crosscourt used 6.3% · won 48% · +4.6±11.5 vs own baseline
  3. FH crosscourt → FH crosscourt used 9.2% · won 47% · +3.3±10.3 vs own baseline
  4. BH crosscourt → BH down the line used 6.0% · won 41% · −2.3±11.5 vs own baseline
  5. FH through the middle → FH crosscourt used 6.3% · won 41% · −3.1±11.3 vs own baseline

Discovered sequences

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

  1. FH crosscourt → BH crosscourt → FH down the line used 1.4% · won 45% · −2.3±12.4 vs own baseline · −6.2 vs tour on the same sequence Disrupted by Amina Anshba (5/15)
  2. FH crosscourt → BH through the middle → FH crosscourt used 1.3% · won 42% · −5.9±12.4 vs own baseline · −17.9 vs tour on the same sequence Disrupted by Amina Anshba (5/16)
  3. FH crosscourt → FH crosscourt → FH down the line used 1.1% · won 41% · −6.3±12.7 vs own baseline · −16.4 vs tour on the same sequence Disrupted by Sara Sorribes Tormo (2/6), Serena Williams (3/6)

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+1.3135
FH to their forehand · rally+0.2171
FH to their backhand · rally−1.1199

Most exposed to

BH to the middle · rally−3.0141
FH to their backhand · rally−2.0156
FH to their forehand · rally+0.9169

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