RallyIQ

Tokyo · R32 · Hard · 19 Oct 2025

Eva Lys v Katie Boulter

64–46 in points · Eva Lys won

Why it went the way it did

Eva Lys won 3.2 more points than Katie Boulter relative to what the serve alone predicted. Katie Boulter's biggest leaks: backhand execution −3.0, slice shot selection −1.4, serve 2nd execution −1.2.

Each shot moves its hitter's chance of winning the point. Those moves are split into direction choice, shot selection and execution, and summed here. Read both columns together: one player's gain is the other's loss.

ShotEva LysKatie Boulter
DirSelExecTotalDirSelExecTotal
Serve 1st +0.1 ±0.0 −1.0 −0.9 ±0.0 ±0.0 −0.9 −0.9
Serve 2nd ±0.0 ±0.0 +0.5 +0.5 ±0.0 ±0.0 −1.2 −1.2
Return −0.1 +0.3 +0.2 +0.4 +0.4 +0.1 +1.8 +2.3
Forehand −0.1 +0.6 +2.9 +3.4 +0.3 +1.2 +1.0 +2.5
Backhand −0.3 +0.1 +0.6 +0.4 −0.2 +0.2 −3.0 −3.0
Slice ±0.0 −0.3 −0.1 −0.5 −0.1 −1.4 +0.7 −0.7
Net −0.1 ±0.0 ±0.0 −0.2 +0.1 +0.1 +0.7 +0.9
Touch ±0.0 ±0.0 ±0.0 ±0.0 ±0.0 ±0.0 ±0.0 ±0.0
All shots −0.5+0.7 +3.0+3.2 +0.6+0.3 −0.9±0.0

Set by set

SetEva LysKatie BoulterNet, Eva
1−0.4−1.9 +1.5
2+3.6+1.9 +1.7

Adaptation

First-serve direction mix set by set, with the share of points each direction won. The scores measure whether the server moved toward the directions that had been winning earlier in this match, set to set and every two to three service games, in points per 100 first serves. Read them as a habit, not a gain: across the tour, a direction's edge in early sets barely predicts the later ones. Whether the returner responded can't be told apart from noise within one match.

Eva Lys serving

SetWideBodyT
1 43% 62% 20% 83% 37% 36%
2 57% 50% 10% 50% 33% 86%

Set to set +0.64 per 100 first serves in sets 2+

Within sets +1.26 per 100 first serves, every two to three service games

Katie Boulter serving

SetWideBodyT
1 38% 67% 13% 50% 50% 38%
2 27% 100% 27% 67% 45% 0%

Counterfactual: the best direction every time

If each shot had gone in the direction that is usually worth most for that stroke and position, this is how many more points each player would expect to win. It's an upper bound: the best direction isn't always on, and the chart can't see the ball's pace or position.

Eva Lys

3.9 points left on the table across 140 shots 2.82 per 100 shots

  1. Serve +1: mid-depth return to your middle hit BH through the middle ×5; BH crosscourt rates higher · 0.31 pts
  2. Return +1: drive to your backhand side hit BH through the middle ×5; BH crosscourt rates higher · 0.24 pts
  3. Return of a 2nd serve, wide, deuce court hit FH through the middle ×2; FH inside-out rates higher · 0.23 pts
  4. Serve +1: mid-depth return to your forehand side hit FH through the middle ×3; FH crosscourt rates higher · 0.20 pts

Katie Boulter

3.7 points left on the table across 160 shots 2.31 per 100 shots

  1. Return of a 2nd serve, wide, deuce court hit FH crosscourt ×5; FH inside-out rates higher · 0.28 pts
  2. Long rally, 9+: drive to your backhand side hit BH through the middle ×4; BH crosscourt rates higher · 0.21 pts
  3. Return +1: drive to your middle hit BH through the middle ×4; BH crosscourt rates higher · 0.18 pts
  4. Return of a 2nd serve, T, ad court hit FH through the middle ×2; FH inside-in rates higher · 0.16 pts