RallyIQ

ATP · Right-handed · 12 charted matches · 2015–2019

Hyeon Chung

Archetype: Grinder · Ad-court T server

Against an average opponent

Serve points won 62.0% ±3.5 raw 55.5% · tour 63.4% · 822 points
Return points won 40.1% ±3.6 raw 38.3% · tour 36.6% · 830 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 −0.27 ±0.10 better than 7% of ATP · raw −0.28
Shot selection −0.08 ±0.26 better than 42% of ATP · raw −0.10
Execution −0.07 ±1.07 better than 65% of ATP · raw −0.31
Tactical adaptability −0.05 first serves toward what's working, set to set · 12 matches
Adaptation speed +0.06 same, every two to three service games · per 100 first serves
Points left on the table 2.47 per 100 shots vs best direction · lower than 66% of ATP

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 4,655 shots.

Shot expected value

The share of points Hyeon Chung 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 46% to the average player · 316 shots

OptionUsedWin %Tour
BH crosscourt 45% 53.4%±6.4 47.6%
BH through the middle 38% 48.0%±7.0 43.7%
BH down the line 11% 47.8%±11.1 46.4%
BH slice through the middle 4% 32.4%±13.2 35.1%

Rally, shots 5–8: drive to your middle

position worth 51% to the average player · 246 shots

OptionUsedWin %Tour
BH through the middle 26% 50.4%±9.0 46.8%
FH crosscourt 22% 55.5%±9.6 52.7%
FH through the middle 17% 43.5%±10.3 47.0%
FH down the line 17% 53.7%±10.4 51.5%
BH crosscourt 13% 48.7%±11.5 49.1%
BH down the line 5% 50.5%±14.3 48.3%

Long rally, 9+: drive to your backhand side

position worth 46% to the average player · 236 shots

OptionUsedWin %Tour
BH crosscourt 46% 45.4%±7.2 48.0%
BH through the middle 33% 50.3%±8.4 43.8%
BH down the line 12% 50.6%±11.9 46.5%
BH slice through the middle 7% 36.2%±13.2 35.1%

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

position worth 44% to the average player · 216 shots

OptionUsedWin %Tour
FH crosscourt 50% 52.2%±7.2 46.6%
FH through the middle 32% 49.2%±8.7 41.5%
FH down the line 13% 36.6%±11.3 44.7%

Serve under pressure

Pressure predictability index +4 How much less varied Hyeon Chung's first-serve direction gets on break points. Positive means easier to read. Based on 99 break-point first serves.

Deuce court

1st serveUsageBreak ptWon when in
Wide 46% 19% ▼ 65% / 73%
Body 15% 22% 59% / 63%
T 40% 59% ▲ 69% / 75%

393 normal · 32 break-point 1st serves

Ad court

1st serveUsageBreak ptWon when in
Wide 38% 30% ▼ 61% / 73%
Body 20% 19% 60% / 63%
T 42% 51% ▲ 65% / 72%

320 normal · 67 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. No measurable response (−0.05 ± 0.15 points per 100 serves for every 10 points of habitual usage), measured from ATP 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
Wide44% 59.0%±5.5 n=185 57% ▲
Body15% 52.8%±8.5 n=64 2% ▼
T41% 54.9%±5.7 n=176 41%

Consistent with an optimal mix (p = 0.43).
Optimal mix: +0.6 per 100 first serves.

Ad court

1st serveUsagePoints wonOptimal
Wide37% 52.2%±6.3 n=142 37%
Body20% 53.5%±7.9 n=78 7% ▼
T43% 57.7%±5.8 n=167 56% ▲

Consistent with an optimal mix (p = 0.45).
Optimal mix: +0.6 per 100 first serves.

Exploitability 0.62 points per 100 first serves What the optimal mix would win over the current one, both courts. More exploitable than 100% of ATP servers. Tested on matches they weren't fitted on, ATP mixes picked this way win 0.33 per 100 first serves on average.

Repeating the previous direction to the same court: −3.0±6.6 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. (307 repeats, 481 switches.)

Return by serve direction

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

ServeCourtDirectionPointsWonvs tour
1stAd courtBody 38 40% +2.9±9.8
1stAd courtT 77 30% +2.3±7.3
1stAd courtWide 106 26% −1.4±6.2
1stDeuce courtBody 38 51% +14.8±10.0
1stDeuce courtT 93 22% −3.5±6.1
1stDeuce courtWide 132 28% +0.7±5.8
2ndAd courtBody 72 56% +6.3±8.1
2ndAd courtT 42 47% −2.4±9.7
2ndAd courtWide 59 48% −0.6±8.7
2ndDeuce courtBody 52 48% −0.6±9.1
2ndDeuce courtT 55 49% −0.4±8.9
2ndDeuce courtWide 59 47% −1.5±8.7

Signature patterns

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

Serve → +1

  1. Wide serve (deuce court) → FH crosscourt used 5.0% · won 62% · +4.5±10.3 vs own baseline
  2. Wide serve (deuce court) → FH down the line used 3.3% · won 57% · −1.1±11.6 vs own baseline
  3. Body serve (ad court) → BH through the middle used 5.7% · won 57% · −0.9±10.1 vs own baseline
  4. Body serve (ad court) → BH crosscourt used 3.7% · won 56% · −1.3±11.4 vs own baseline
  5. T serve (ad court) → FH crosscourt used 4.3% · won 56% · −1.8±10.9 vs own baseline

Return

  1. vs T serve (ad court) → FH through the middle, mid used 7.8% · won 50% · +7.0±10.6 vs own baseline
  2. vs wide serve (deuce court) → FH through the middle, mid used 7.8% · won 48% · +5.3±10.6 vs own baseline
  3. vs T serve (deuce court) → BH through the middle, mid used 7.0% · won 44% · +0.8±10.8 vs own baseline

Rally, consecutive own shots

  1. FH crosscourt → BH through the middle used 3.7% · won 57% · +6.5±10.1 vs own baseline
  2. FH through the middle → FH crosscourt used 4.5% · won 57% · +5.7±9.5 vs own baseline
  3. BH through the middle → FH crosscourt used 5.1% · won 55% · +3.9±9.1 vs own baseline
  4. FH crosscourt → FH crosscourt used 5.9% · won 54% · +2.9±8.7 vs own baseline
  5. BH through the middle → BH crosscourt used 6.5% · won 54% · +2.7±8.4 vs own baseline

Discovered sequences

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

  1. FH crosscourt → FH crosscourt → FH crosscourt used 1.8% · won 55% · +6.4±9.7 vs own baseline · +9.9 vs tour on the same sequence Disrupted by Roger Federer (3/7), Alex De Minaur (5/9)
  2. BH crosscourt → BH through the middle → FH crosscourt used 0.8% · won 58% · +9.4±12.1 vs own baseline · +16.9 vs tour on the same sequence Disrupted by Alex De Minaur (4/6), Novak Djokovic (4/6)
  3. FH crosscourt → FH down the line → BH through the middle used 0.8% · won 55% · +6.0±12.1 vs own baseline · +18.0 vs tour on the same sequence Disrupted by Novak Djokovic (7/10)
  4. BH through the middle → FH through the middle → FH through the middle used 0.6% · won 55% · +6.7±13.0 vs own baseline · +19.6 vs tour on the same sequence Disrupted by Nikoloz Basilashvili (5/7)
  5. BH through the middle → FH down the line → BH through the middle used 1.0% · won 53% · +4.6±11.5 vs own baseline · +14.5 vs tour on the same sequence Disrupted by Novak Djokovic (3/7)
  6. BH through the middle → FH crosscourt → FH through the middle used 0.8% · won 54% · +5.0±12.2 vs own baseline · +19.7 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

BH to the middle · return+2.4182
FH to the middle · return+1.2171
FH to the middle · rally+1.0194
BH to the middle · serve +1+0.9123
BH to the middle · rally+0.5318

Most exposed to

FH to the middle · return−2.9175
BH to the middle · return−2.2200
FH to their backhand · serve +1−0.9159
FH to their backhand · rally−0.8399
Wide 1st serve · deuce court−0.5208

Active players who are best at the shot in the top weakness: Roman Safiullin, Tomas Machac, Miomir Kecmanovic, Roberto Bautista Agut, Tommy Paul

Tactical fingerprint

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

Through the middle34%
Avg rally length4.6
T serves · ad43%
Deep returns28%
Wide serves · deuce44%
1st serve in61%
Unforced errors / shot9.5%
Serve & volley0%
T serves · deuce41%
Drop shots / shot0.8%
Point-ending shots20.4%
Points at net7%
Chipped returns8%
Backhand slice10%
BH down the line16%
Run-around forehands9%
Forehand share47%
FH down the line25%
Wide serves · ad37%

Plays most like

  1. Miomir Kecmanovic 2019–2026 plan v
  2. Alex De Minaur 2016–2026 plan v
  3. Alexandre Muller 2023–2025 plan v
  4. Emil Ruusuvuori 2021–2024 plan v
  5. Ilya Ivashka 2018–2023 plan v
  6. Botic Van De Zandschulp 2019–2026 plan v
  7. Andreas Seppi 2008–2021 plan v
  8. Diego Schwartzman 2015–2025 plan v

Closest from another era

  1. Aaron Krickstein 1989–1995
  2. Michael Chang 1989–1998
  3. Magnus Norman 2000–2001

Charted matches