He Threw 104. The Box Score Said He Climbed Three Levels. It Did Not.

By Sean McKnight · reported from Las Vegas Ballpark

What does one great pitch actually tell you? On September 26 I sat at Las Vegas Ballpark and watched number 44 throw seventeen fastballs. Every one came in at 101.5 or better. The fastest hit 104.

Two questions came with it. How often does a pitcher climb from Single-A to Triple-A in a single season? And does being tall explain throwing that hard?

Most people assume the way to answer a question like this is to find other pitchers who did the same thing. That is the natural move and it is the wrong one, because it counts only the people you already noticed. The answer comes from counting everybody who belongs in the calculation — and once we did, it turns out the box score was describing something that never happened.

First, check what actually happened

The pitcher was Jarlin Susana, of the Rochester Red Wings. He is listed at six foot six and 235 pounds — not the six foot eight I heard at the ballpark — and he is 22.

His season line reads High-A, then Double-A, then Triple-A. That looks like a prospect climbing three rungs in one summer.

The transaction log says otherwise, and we went and read it. He had already reached Double-A in April 2025. His August 2026 appearance at High-A Wilmington is listed as a rehabilitation assignment — he was coming back from the 60-day injured list. Then in September he moved up to Triple-A.

So: one genuine promotion, not three. The season line is accurate and the story it tells us is wrong, which is a combination we should all find unsettling.

This matters beyond one pitcher. Suppose you wanted to study how often prospects advance quickly. Count rehab stops as promotions and you have put the wrong players in your sample before computing anything. The trouble happens when you classify, not when you calculate.

Promoted compared with whom

Say you want to know whether fast promotion predicts a big-league career. First you have to define fast. Starting at Single-A and reaching Triple-A is one journey; starting at High-A is another. You have to strip out rehab trips. You have to separate a first climb from a return to a level already reached.

Then you have to decide what counts as success. One big-league appearance? Fifty innings? Three seasons? A pitcher can clear the first bar without coming near the third.

And then the part people skip. The denominator depends on the question. Asking how often pitchers climb from A to Triple-A means starting with every eligible A-level pitcher. Asking how often those climbers reach the majors means starting with the climbers. Same subject, different bottom of the fraction, wildly different answer.

A list of famous pitchers who moved fast cannot settle it. It leaves out every player whose name you never learned — and that is the group the answer depends on.

Tall compared with whom

Now the second question. Susana is six foot six. Félix Bautista is six foot eight and has been reported at 102 and 103. Yordano Ventura was five foot eleven and also touched 102. Those examples prove that extreme velocity happens at several heights. They do not tell you how common it is at any of them.

Suppose a study found that most pitchers reaching 102 were tall. Watch what that does and does not mean.

Eighty percent of the hardest throwers are tall. And being tall does not help at all. Both come from the same twenty pitchers, and the second is the answer to the question we actually asked.

The 80% only counts the pitchers who already threw 102. It never asks how many tall pitchers there were to begin with. The share of fast pitchers who are tall is not the share of tall pitchers who are fast.

What the research can and cannot say

A 2022 study in PLOS ONE measured 64 adult pitchers at a professional tryout in Taiwan. Height mattered in a model that also used jump and sprint tests, and together those measures accounted for about 23% of the differences in velocity.

Read that carefully. It does not mean height explained 23%. It does not mean you could pick out 23% of future big leaguers. It means those measurements together covered part of the variation in that sample — and most of the variation stayed unexplained.

There is a deeper problem too. Pro pitchers have already survived years of selection. A short pitcher who got that far probably has something else going for him. Study only the survivors and you get a different answer than studying everyone who started out.

What to take home

Let the thing you noticed start the investigation, not finish it. Check what actually happened before you explain it. Decide who belongs in the comparison. Then count the denominator — including everyone we never had a reason to notice, because they are the ones holding the answer.

You can use this tonight, on any number a broadcast gives you. When somebody says most of the people who did X share some trait, ask the other question: of everyone with that trait, how many did X? Those are different fractions and only one of them is usually being sold to you.

I went to the ballpark to watch baseball. Number 44 gave me a reason to think about statistics instead. The fastball was spectacular; the questions it raised were worth the trouble.

What we are not claiming. We have not measured how often pitchers really do climb three levels, or how much height really contributes to velocity. Both would need a proper game-level study with the follow-up period held equal, and neither is done here. The height numbers in the figure are invented to show the arithmetic, and are labeled as such.

Susana’s details come from his official profile and transaction history; the velocity from the league’s own report. More at thesportspage.net.