Baseball intelligence
Tunneling explained
How close a pitcher’s average fitted pitch-type paths are during the final part of flight, in inches. Lower means closer paths.
Definition and interpretation
For each pair of competitive pitch types with fitted pitches, average their horizontal and vertical path separation at 150, 175, 200, 225, 250, 275 and 300 milliseconds before each pitch’s own plate arrival. A type’s score averages its gaps to every other competitive type with fitted pitches, weighted by those other types’ fitted pitch counts; the arsenal score averages type scores by fitted competitive usage.
Lower inches mean the average fitted paths stayed closer during the measured window. A pitch type is compared with every other competitive type with fitted pitches, not only its nearest partner. With exactly two competitive types with fitted pitches, their type scores are equal by definition.
Coverage and limits
MLB regular seasons from 2008 onward, where source 3D velocity and total acceleration support reconstruction. Intentional balls (IN) and pitchouts (PO) remain available as context paths but are excluded from scores, score partners, intervals, coverage denominators and comparison cohorts. Paths are pitch-type means, not observed pitch sequences or what a hitter saw. Coverage support requires at least 30 fitted pitches across three games, 80% source retention and a covariate-balance check; the arsenal needs two supported types covering at least 90% of competitive source usage and 80% retention. Thin or missing evidence remains limited or unavailable; no values are filled in.
Observed fitted arsenal with at least two nonempty competitive types; coverage limits are shown. No public leaderboard.
Explore paths, pitch partners and available scores in the pitcher’s exact-season Advanced view. Coverage and sample limits appear beside the results.
Methodology, coverage and source references · Source attribution
Find a player and open the exact-season Scouting Report →