Fire Starter Score

Which players ignite runs when they step on the floor

The Idea

Certain players when they get subbed in, or are on the court just cause momentum shifting runs. These are game defining moments that swing win probability. The idea behind the fire starter statistic is to identify who is on the court when these runs happen, and who contributes to them.

How It Works

Detect runs with sliding possession windows

Every possession of the season is laid out in order. Starting from each possession, windows of 6, 8, 10, 15, and 20 possessions are checked. A window qualifies as a run when the team scores at least 70% of all points in the window and outscores the opponent by 6 or more. Checking multiple window sizes catches both quick 8–0 bursts and longer sustained 18–4 stretches — for each starting point, only the highest-scoring window is kept.

Score each run by quality, not just size

A 10–0 run in a tie game against the best defense in the league is not the same as a 10–0 run up 25 against a bottom-five defense. Each run gets a single score that bakes in all of that context:

Run Score

run score = margin × ratio × leverage × opponent weight

marginPoints scored minus points allowed during the run. A 14–2 run has a margin of 12.

ratioShare of all points in the window scored by the running team. A pure 10–0 run (ratio 1.0) beats a 14–4 trade-off (ratio 0.78).

leverage1 / (1 + 0.1 × |score margin when the run starts|). A run that starts in a tie game gets full weight (1.0); a run that starts up or down 20 gets about a third (0.33). Garbage-time runs barely count.

opponent weightLeague-average defensive rating divided by the opponent's defensive rating. Going on a run against an elite defense is worth more than feasting on a bad one.

Credit the players who fueled it

For every kept run, play-by-play data identifies who actually scored. Made shots and free throws during the run's clock window. Each player on the floor gets a share of the run's score: scorers split credit proportional to their scoring actions, while players on the floor who didn't score get a small 10% baseline for their part in the stops, screens, and spacing that box scores miss. A player's credit for one run is the run score × their involvement share.

Normalize per minute played

Summing credit across the season would just reward heavy minutes. Instead, total weighted credit is divided by minutes played (per 1,000 minutes). That is the Fire Starter Score — run-igniting impact per minute on the floor. This is what lets a 18-minute-a-night bench gunner outrank a 36-minute starter.

A Worked Example

A team rips off a 12–2 run (margin 10, ratio 0.86) starting from a 4-point deficit (leverage 0.71) against a defense 5% better than league average (opponent weight 1.05).

Run score = 10 × 0.86 × 0.71 × 1.05 ≈ 6.4. If one player scored 8 of the 12 points across 4 of the 6 scoring actions, they collect roughly 6.4 × 0.67 ≈ 4.3 toward their season total. The four teammates on the floor split smaller shares.

Reading the Stat

Runs Involved — how many distinct runs the player was on the floor for
Total Run Score — sum of the scores of every run they were part of
Fire Starter Score — weighted run credit per 1,000 minutes; the headline number

High scores point to players whose presence coincides with — and whose scoring drives — momentum swings. Bench microwaves, energy bigs, and heat-check guards tend to rise here even when their per-game averages look modest.

Caveats

On-floor credit is correlation, not strict causatio. Role players riding a star's run still collect the baseline share
Credit flows through scoring actions, so run-starting defense (deflections, stops) is captured only indirectly
Low-minute players can post inflated per-minute scores off small samples. Check Runs Involved alongside the score

See the Fire Starter leaderboard

Every player and team, ranked by run-igniting impact.

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