The Defender in Second Place: What 2024 J1 Key Passes Reveal About Position Filters

The second-highest key-pass rate in this 2024 J1 sample belongs to a player filed under "defender." A recruitment screen that starts by selecting midfielders and forwards would never have returned him. That is a workflow problem, not a data curiosity.

Why key passes rather than assists

An assist requires a teammate to score. That makes it a joint output of the passer and the finisher, and in a single season the finisher contributes a large share of the variance. A creator playing behind a striker converting at 33% will accumulate assists faster than an identical creator playing behind one converting at 18%, and no amount of care in reading the assist column separates the two.

A key pass — a pass leading directly to a shot — stops the measurement one event earlier. It records that the passer created a shooting opportunity, and leaves what happened next out of it. The sample is also several times larger, since most created chances do not become goals.

Neither property makes key passes a good metric on its own. They make it a better starting metric, which is a narrower claim.

The filter that runs before the metric

Matheus Sávio at the top is unremarkable. He is an on-ball creator playing as one, with a 7.39 average rating placing him among the top three of this sample. The metric agrees with the label.

Ryo Hatsuse is the case worth the time. He produced 2.37 key passes per 90 and finished near the top of the league with 7 assists, from a position recorded in the data as defender. Full-backs functioning as primary chance creators is not a new idea — it has been standard in the top European leagues for a decade — but the point here is not tactical. It is procedural.

Most recruitment screens narrow by position before they rank by anything. A department looking for creativity selects midfielders and forwards, sorts by key passes or assists, and reads the top of the list. Run that sequence on 2024 J1 and Hatsuse is gone at step one, before any metric touches him. He does not rank low; he never enters the ranking.

The correction is not to distrust position data. It is to rank first and filter second — or at minimum to run creativity screens across all outfield positions once, and treat any defender appearing near the top as a case to inspect rather than a labelling error to discard.

Involvement volume: reading creation and shooting together

One player in this table also appears in our 2024 J1 shooting data, which allows both axes to be read at once.

Takashi Usami took 66 shots in 2,669 minutes — 2.23 per 90 — and added 2.33 key passes per 90. Combined, that is roughly 4.6 shot involvements per 90, either taking the attempt himself or supplying it. He also carried the highest average rating in this sample at 7.58, at 33 years old.

Set against his finishing, the picture is coherent. Usami converted 18.2% of his shots, essentially identical to the 18.4% average across the 36 J1 players with 30+ attempts. He is not an efficient finisher by any reading of that number. What he is, in this data, is a player around whom an unusually high share of his team's shooting passes — which is a different asset, valued differently, and one that depends more heavily on the tactical role a new club would give him.

Age is the constraint that dominates the transfer case rather than the performance case. A 33-year-old with elite involvement volume and average conversion is a short-horizon signing, and any club reading these numbers should price them on that horizon rather than on the rate alone.

Concentrated supply versus distributed supply

Two clubs in this table show opposite shapes, and the difference carries a recruitment implication.

Gamba Osaka occupy second and third on the chart through Hatsuse (2.37) and Usami (2.33). Their creation is concentrated in two players. Sanfrecce Hiroshima distribute it: Shunsuke Higashi contributed 2.02 key passes per 90 with 8 assists, alongside Mutsuki Kato's 7 assists, with no single figure dominating.

For a buying club this is a question about attribution. A high key-pass rate produced inside a concentrated system may be partly a property of that system — the player is the designated outlet because there is no alternative — and may not survive a move into a squad where the ball is shared differently. A comparable rate produced inside a distributed system faced competition for those touches. Neither shape is better. They imply different things about how much of the number belongs to the player.

What a key pass does not record

The metric counts shots created. It says nothing about the shots themselves.

A pass that draws a speculative strike from 30 yards is scored identically to one that puts a striker through on goal. Without expected-assists data — which this dataset does not include — a key-pass column measures the volume of shooting a player generates, not the danger of it. Two players on 2.02 per 90 can be doing entirely different jobs.

The more consequential omission concerns set pieces. Corners and attacking free kicks are recorded as key passes when a shot follows, and this dataset does not separate them from open play. A designated set-piece taker accumulates key passes at a rate that has limited bearing on his creative ability in open play.

This matters most for exactly the player this article is about. Full-backs are frequently set-piece takers. We cannot state from this data what share of Hatsuse's 2.37 came from open play, and we are not going to estimate it. Until that split is available, his figure should be read as a reason to pull footage, not as a settled creative profile. The same caution applies to every name in the table; it simply applies hardest to the one whose position label makes set-piece duty most likely.

A working sequence

1. Rank before you filter. Run creativity metrics across all outfield positions at least once. Position-first screening is where full-backs and wide defenders disappear.

2. Use key passes as the entry metric, not assists. Larger sample, and it excludes the finisher's contribution.

3. Resolve set-piece share before believing the rate. For any defender or wide player near the top of a key-pass table, this is the first question, not the last.

4. Read creation and shooting on the same player. Involvement volume — key passes plus shots per 90 — describes how much of a team's attacking output runs through him.

5. Check whether supply is concentrated. A rate produced as a team's only outlet transfers less predictably than the same rate produced in competition.