RallyIQ

Game plan

Marta Kostyuk v Lulu Sun

Every number combines what Marta Kostyuk does well with what Lulu Sun allows, each measured against the tour average and shrunk toward it when the sample is thin. Flip perspective

Forecast

Marta Kostyuk wins, best of 3 64%90%: 32%–88% · best of 5: 67%
Serve points won 63.5% / 60.8% Marta / Lulu · tour 58.1%
Strengths only, no similarity priors 61%serve 63.3% / 61.1%

Each player's serve and return strength is fitted against every opponent they were charted against, so a record built on weak opponents counts for less. At least one of them is no longer active or has too little charted in the last three seasons, so both are compared on their careers. The result is then nudged by Marta Kostyuk's record against Lulu Sun's tactical lookalikes and in their charted head-to-heads (lookalikes: +8.9 on serve, +12.0 on return vs expectation (92 points)). A game-by-game Markov chain turns point odds into match odds; the 90% range covers the uncertainty in the two strengths, not the nudges. Charted matches lean toward big events, so treat this as a scouting estimate, not a betting line.

Head to head, per 100 shots

CareerMartaLulu
Direction choice−0.06 ±0.05
better than 43%
−0.04 ±0.13
better than 48%
Shot selection+0.13 ±0.09
better than 60%
+0.31 ±0.35
better than 79%
Execution−0.34 ±0.29
better than 41%
−0.39 ±1.24
better than 39%
Points left on the table2.69 ±0.07
lower than 36%
2.91 ±0.34
lower than 16%

Each player's career against an average tour player in the same position, adjusted for opponent strength, with a 90% margin (shots clustered by match). Points left on the table is the gap to the best-value direction for the same stroke, so lower is better. Percentiles are within each player's own tour. A side is highlighted only when the gap is larger than the margin on the difference.

Serve plan

The share of points the server wins when a first serve lands in that direction (hover a rate for its 90% interval; ± is the 90% margin). "Matchup" combines the server's rate with how this returner handles that serve. "Optimal" is the mix that wins most against this returner once they start reading a habit, at the response measured across the tour, and only within the range servers' habits actually vary. The gain over the current mix is how exploitable that mix is.

Marta Kostyuk serving

Deuce court

1st serveNowMarta winsv LuluMatchupOptimal
Wide36%70%70%74.5%±5.951% ▲
Body24%60%53%55.8%±9.59% ▼
T40%72%71%74.5%±8.240%

Optimal v Lulu Sun: +1.9±1.0 per 100 first serves (faults included) over the current mix. Serving T every time would read +4.6 per 100 first serves in before the returner adjusts.

Ad court

1st serveNowMarta winsv LuluMatchupOptimal
Wide47%73%71%77.4%±6.662% ▲
Body26%58%58%59.8%±9.611% ▼
T27%64%65%64.6%±7.827%

Optimal v Lulu Sun: +1.3±1.0 per 100 first serves (faults included) over the current mix. Serving wide every time would read +8.0 per 100 first serves in before the returner adjusts.

Lulu Sun serving

Deuce court

1st serveNowLulu winsv MartaMatchupOptimal
Wide30%67%63%64.3%±9.342% ▲
Body24%53%57%52.1%±9.79% ▼
T45%69%68%68.9%±7.749% ▲

Optimal v Marta Kostyuk: +0.6±1.0 per 100 first serves (faults included) over the current mix, inside the 90% margin. Serving T every time would read +5.5 per 100 first serves in before the returner adjusts.

Ad court

1st serveNowLulu winsv MartaMatchupOptimal
Wide42%73%64%71.4%±7.741%
Body16%62%58%63.4%±11.01% ▼
T42%84%61%82.2%±7.158% ▲

Optimal v Marta Kostyuk: +1.0±1.1 per 100 first serves (faults included) over the current mix, inside the 90% margin. Serving T every time would read +7.5 per 100 first serves in before the returner adjusts.

Return plan

Value of each return, in points per 100 returns against an average return of the same serve (direction, court, surface): the tour's result with that return, the returner's own edge with it, and what this server gives up when it comes back to that side. Returns with no charted direction are left out, so values compare with each other rather than with zero. Depth isn't a choice here: missed returns have no depth. Serve quality isn't charted, so a block through the middle partly reflects the serve that forced it.

Marta Kostyuk returning

1st serve to the forehand

ReturnNowTourOwnv LuluValue
FH through the middle41%+4.2+0.6−0.1+4.6±2.6
FH crosscourt19%+5.3+0.5−2.7+3.1±3.8
FH slice through the middle17%−6.7+1.4−1.5−6.9±2.1
FH down the line12%+1.5+4.8−2.8+3.5±4.2
FH slice crosscourt8%−6.6+0.9+0.6−5.1±2.5

Lean FH through the middle: +3.5±1.8 per 100 returns v the current mix (1346 returns charted)

1st serve to the backhand

ReturnNowTourOwnv LuluValue
BH through the middle52%+6.0−0.2+1.2+7.0±2.4
BH crosscourt29%+7.7−2.1−1.4+4.2±3.1
BH down the line10%+2.2−1.1−5.2−4.2±4.5
BH slice through the middle4%−6.2−0.1+1.3−5.0±2.4
BH slice crosscourt3%−4.2−0.7+2.1−2.8±2.4

Lean BH through the middle: +3.1±1.5 per 100 returns v the current mix (969 returns charted)

2nd serve to the forehand

ReturnNowTourOwnv LuluValue
FH through the middle41%−3.2+1.5+2.4+0.7±2.9
FH crosscourt28%+0.5−1.0−1.6−2.1±3.9
FH down the line25%−0.6+0.7−7.2−7.1±5.1
FH slice through the middle4%−15.2+0.6+1.7−12.9±1.9
FH slice crosscourt2%−14.9+0.6±0.0−14.3±1.5

Lean FH through the middle: +3.7±2.4 per 100 returns v the current mix (362 returns charted)

2nd serve to the backhand

ReturnNowTourOwnv LuluValue
BH through the middle46%−2.6−2.6−0.1−5.3±2.5
BH crosscourt30%+1.5−1.1+2.5+2.8±3.5
BH down the line19%−0.5+1.0−2.3−1.8±5.0
FH inside-out2%+1.4±0.0−7.2−5.8±3.8
FH through the middle1%−2.7−0.2+2.4−0.4±2.3

Lean BH crosscourt: +4.9±2.8 per 100 returns v the current mix (471 returns charted)

Lulu Sun returning

1st serve to the forehand

ReturnNowTourOwnv MartaValue
FH through the middle59%+4.2−0.2+0.7+4.7±2.6
FH crosscourt26%+5.3+0.9−2.7+3.5±3.8
FH down the line15%+1.5−3.0−3.9−5.4±3.7

Lean FH through the middle: +1.8±1.5 per 100 returns v the current mix (95 returns charted)

1st serve to the backhand

ReturnNowTourOwnv MartaValue
BH through the middle46%+6.0−1.6−0.2+4.2±2.3
BH crosscourt27%+7.7+2.1−2.8+7.0±3.3
BH slice through the middle12%−6.2±0.0−2.3−8.5±2.4
BH slice crosscourt8%−4.2−3.5−1.6−9.3±2.8
BH down the line7%+2.2−0.5−1.5+0.3±3.6

Lean BH crosscourt: +4.9±2.7 per 100 returns v the current mix (214 returns charted)

2nd serve to the backhand

ReturnNowTourOwnv MartaValue
BH crosscourt48%+1.5−1.3−1.3−1.1±3.6
BH through the middle46%−2.6−0.1−0.1−2.8±2.4
FH through the middle6%−2.7−0.5+0.3−2.8±1.6

Lean BH crosscourt: +0.9±2.2 per 100 returns v the current mix (87 returns charted, inside the 90% margin)

Rally plan

Edge, in points per 100 shots: the hitter's skill with the shot (own) plus how much the receiver usually gives up against it (theirs), both measured against the tour average on grass. Each player's grass record is shrunk toward their all-surface one, so a thin sample on it moves the numbers only a little.

Marta Kostyuk

Favour

ShotEdgeOwnTheirs
FH to their backhand · serve +1+5.6±5.5+3.7+1.9
FH to their backhand · rally+4.7±5.4+2.2+2.5
FH to their backhand · return +1+3.6±6.2+0.1+3.5
FH to the middle · rally+2.7±3.7+1.1+1.6
BH to the middle · rally+1.8±3.3+1.6+0.3
BH to their backhand · rally+1.6±5.0+3.5−1.9

Avoid

ShotEdgeOwnTheirs
BH to their forehand · return−4.2±6.3−3.1−1.2
BH to the middle · return−2.0±3.4−2.6+0.6
BH to their forehand · rally−1.4±6.3−2.7+1.3
FH to the middle · serve +1−0.9±3.8+1.4−2.3
BH to the middle · serve +1−0.3±3.8−1.3+1.0

Lulu Sun

Favour

ShotEdgeOwnTheirs
FH to their forehand · serve +1+4.9±5.4+3.8+1.1
FH to their forehand · rally+2.0±5.1−0.6+2.6
FH to the middle · rally+1.3±3.6+1.4−0.1
FH to their backhand · rally+1.0±5.1+4.2−3.2
FH to their backhand · return +1+0.8±6.2+3.0−2.2
FH to their backhand · serve +1+0.2±5.9−1.0+1.1

Avoid

ShotEdgeOwnTheirs
BH to the middle · rally−7.5±3.5−5.7−1.8
BH to their forehand · rally−6.6±5.9−1.4−5.2
BH to the middle · return−2.6±3.5−2.8+0.2
BH to their forehand · return−1.6±6.0+2.6−4.2
FH to the middle · serve +1−1.3±3.9−1.5+0.3

Against Lulu Sun-like opponents

Marta Kostyuk vMatchesServe pts wonReturn pts won
All charted opponents–58.2%44.7%
Players most similar to Lulu Sun1 69.6%56.5%

Similar by tactical fingerprint: Alexandra Eala, Diana Shnaider, Xin Yu Wang, Robin Montgomery, Katie Boulter, Arianne Hartono, Jule Niemeier, Caroline Garcia, Eugenie Bouchard. When two players have rarely met, their records against these lookalikes fill the gap.