What is the single best pitch thrown in Japanese pro baseball? I wish to God I knew. But while best is a decision we can only guess at, one can make a reasonable estimate about how effective pitches are based on how they shape the run-scoring potential in innings. Every called ball increases it, every called or swinging strike decreases it.

If one had access to Trackman data that allowed us to calculate the value of batted balls based on their speed and trajectory, one could assign the same value to batted balls regardless of the quality of the defense behind each pitcher.

That is not available, and with the knowledge that the end results of batted balls are subject to some randomness, I evaluate them mostly on the end result, the number of bases gained or lost, the number of outs made, and the number of runs scored, with a tiny amount as the average value of fair balls hit into the outfield or the infield and bunts.

The valuations are related to the base-out situations, and counts, and park adjustments, and each individual pitch is given a value based on the increase or decrease in run expectation from the state prior to the pitch.

With the exception of about 20 pitches from one game in 2020 and an entire game in 2023, I am compiling a record of every pitch thrown in Japanese pro baseball from 2020 to the present.

Let’s start with the big picture, the best pitches 2,000 minimum thrown between 2020 and 2024. The average velocities are in kilometers per hour, while the swing-and-miss percentage is of all pitches offered at.