Archive file · Specimen No. 05

Splitter

It looks like the fastball the whole way, then the floor drops out at the plate.

Open this like an archive drawer: grip first, source attached, shape in words, no invented spin or movement numbers. The file exists so the hold can keep moving forward.

Shape read

Holds flat · arm-side run

Rides the fastball's line out of the hand, then falls off the table late and hard, a trap-door drop that arrives just under the barrel. With the backspin stripped away it tumbles instead of carrying, and the floor seems to vanish at the last instant.

ShapeReputable analysis

The index and middle fingers are wedged to opposite sides of the ball, spread wide on the outside of the leather, wider and farther back than a forkball, with the ball coming off the inside of the fingers rather than the fingertips. Thrown with the arm action of a fastball.

OffspeedThe trap doorMagnus, weak

GripReputable analysis

Open the grip file All pitches

Archive Drawer / Grip Lab

The artifact in the hand

Lead with the hand. The fingers on the ball below are the sourced contacts, solved onto the seam. Drag the ball, or use the view buttons.

Reputable analysisWikipedia, Split-finger fastball

View

Hand

Keyboard: arrows switch views · F flips the hand · H lifts it

01Wedge your index and middle fingers wide, to opposite sides of the ball, outside the seam tracks rather than directly on them.
02Let the ball sit up between them, farther forward than a deep forkball.
03Rest your thumb underneath, centered between the split fingers.
04Throw it with fastball arm speed and a firm wrist; the split kills the spin for you.

What it should feel like

Throw it as hard as the fastball. The wide split does the work, not a softer arm.

Grip geometry is schematic and shows the wide split-finger family; the depth and spread vary with hand size, and large hands make it easier. On shorter fingers the split can look close to a two-seam; read whether the fingers sit outside the seam tracks instead of directly on them.

Ball depth

Neutral depth

Spacing

Wide spacing

The sourced grip, in full

Reputable analysisWikipedia, Split-finger fastball

Paraphrased from Wikipedia (Split-finger fastball) and corroborated by Driveline; not quoted.

A descendant of the forkball, the splitter is held farther forward in the hand with a wider split between the fingers, which is why it can be thrown harder than the deep-jammed forkball.

Reputable analysisWikipedia, Split-finger fastball

Wikipedia describes the splitter as a faster, shallower relative of the forkball.

Driveline files the splitter under the same family and notes its defining trait: it spins far less than a fastball. The lost backspin, not any added force, is what makes it drop.

Reputable analysisDriveline Baseball Help, Pitch Grips: Splitters

Paraphrased from Driveline. Described as a loss of spin, in words, not a measured figure.

Bruce Sutter's unusually large hands let him spread the split far enough to execute it; instructor Fred Martin taught it to him, and Sutter never changed the grip after the first day.

Reputable analysisNational Baseball Hall of Fame, Sutter remembered as pioneer of the split-finger

From the Hall of Fame tribute to Sutter; the hand-size detail is corroborated on his Wikipedia page.

Release Room

Translate the hold into a release

Grip shape only matters if the release makes sense. Read pressure, thumb support, and ball depth before you read the pitch shape.

Hold

The ball sits up between the split fingers, farther forward than a forkball.

Pressure

Half of the wide split

Leave

Throw it like the fastball and let the wide split deaden the spin.

It is thrown with the arm speed and release of a fastball. The wide split and a stiffer wrist dramatically reduce the backspin, weakening the Magnus lift that keeps a four-seamer riding, so gravity wins late and the ball drops sharply, the classic trap-door look.

Reputable analysisThe Conversation, the physics of Kevin Gausman's splitter

Paraphrased from The Conversation's physics breakdown of Gausman's splitter.

Movement

It barely rides, so it falls almost like a spinless ball, late and under the barrel.

The read is shape, not a gauge. The spin words explain why it moves that way, and every prose claim still carries its source.

Shape

Holds flat · arm-side run

Reputable analysisThe Conversation, the physics of Kevin Gausman's splitter

Spin words

A fastball-like backspin axis out of the hand, so the two look identical at release; the deception lives in matching the fastball's tilt until the pitch separates in flight.

Reputable analysisWikipedia, Split-finger fastball

Craft read

The wide grip strips the backspin a fastball lives on, so the ball stops riding and gravity takes it down late. The hitter has already swung where the fastball should be, and the pitch falls under the barrel.

The one teaching sentence

Because it leaves the hand looking like the fastball, the hitter starts a fastball swing; then the lost backspin lets gravity pull it under the barrel at the last instant. Take the split away or put the backspin back and it just becomes a slow fastball.

Reputable analysisThe Conversation, the physics of Kevin Gausman's splitter

Master Files

Three ways the same pitch wins

From the pitch's pioneer to its modern swing-and-miss kings. The visual is our own seam schematic. What sets each arm's splitter apart is in the read and the hand, not a gauge.

Bruce Sutter

The pioneer. Instructor Fred Martin taught him the split-finger, and he rode it to the Hall of Fame as one of the first dominant closers.

The first to ride this pitch to the Hall of Fame, and the proof of concept for the whole grip — a closer who turned one trap-door drop into a career after his fastball left him.

Reputable analysisWikipedia, Bruce Sutter

Roger Clemens

Added the splitter in the nineties, nicknamed it "Mr. Splitty," and made it his out pitch, one of the most devastating in the pitch's history. He has his own chapter in the Craftsmen.

Late-career reinvention in one pitch: he bolted "Mr. Splitty" onto a power arsenal and kept missing barrels long after the pure heat would have faded, which is why he stayed an ace into his forties.

Official dataWikipedia, Roger Clemens

Kevin Gausman

The modern volume king. His splitter has produced more swinging strikes than any other pitcher's since the Statcast era began, by a wide margin.

The most prolific swing-and-miss splitter of the tracked era, and not close — he throws it like a fastball over and over and hitters keep waving under the late drop because the look never tips.

Reputable analysisJays Journal, Gausman's splitter is one of the best pitches in baseball

Shohei Ohtani

The unhittable one. His trap-door splitter became, in a single season, about as unhittable as a pitch gets.

A splitter thrown hard enough to look like premium heat until the floor drops — for one season hitters who put a swing on it almost never made contact, which is as close to unhittable as the pitch comes.

Reputable analysisMLB.com, Ohtani's splitter still the most unhittable pitch/ 2021

The colophon

Every claim, sourced

Nothing here is marked right or wrong. It is marked by where it came from and how confident the source is. A broken citation throws at build, so a dead source never reaches you.

Official dataPitcher's own wordsCoach-observedReputable analysisSecondhand, attributed

108 double stitches, 216 individual · seam-informed schematic · as of the dates above

The arm who owned it

C-03 · 1984-2007

Roger Clemens

Split-finger fastballOpen the file →

Others in the offspeed

Circle changeup Forkball Knuckleball Eephus

Tier 03 / Field Notes

Field notes from the bullpen.

Every pitcher fiddles. A thumb creeps lower, a seam catches more leather, a cue from a coach suddenly makes the pitch move. Pitch Atlas files those experiments as specimens with context, so the small discoveries stop disappearing into group chats and comment sections.

How notes rank

Evidence and context, never who shouts loudest.

There is no single correct way to throw a pitch, but there are better and worse claims. A funny line should never outrank a tested grip. So notes do not rise on raw votes. They rise on weighted signals - provenance and adoption first.

35%
Provenance
Source tier and evidence. A coach-observed note with a link outranks an unverified hunch with none.
20%
Adoption
How many other pitchers independently tried the same tweak. Real replication, not passive clicks.
20%
Usefulness
Marked useful, measured against views so a small loud crowd cannot stuff the rank.
15%
Context match
How close a note is to your level, slot, and pace context. Computed in your session, never stored.
10%
Community confidence
Considered practice: a real sample size behind the claim, not one good bullpen.

The vocabulary

Field Note: One pitcher's report on a grip variant.
Variant: A specific, named change from the canonical grip.
Tried This: A second contributor replicating the tweak.
Coach Note: A coach reporting on an arm they work with.
Source Challenge: A standing request for the evidence behind a claim.
Provenance: The source tier and evidence that set a note’s rank.
Adoption: How many others independently tried it.
Needs Evidence: A note flagged for missing support, kept visible.

Your bullpen card

0 pts

Filing as an unclaimed contributor · anonymous.

Log a field note

Throw the splitter with a wrinkle of your own? Add it. Label where it comes from: your own report, a coach, or a hunch. Keep it to grip and technique only. No medical, injury, workload, or youth-training prescriptions. Sourced, not corrected.

Field notes for the splitter

Keeping the bullpen honest

Field Notes are live for grip and technique only. No medical, injury, workload, or youth-training prescriptions. Every note carries a source and confidence label, and contributors can report problems. No abuse, no personal attacks, no off-topic spam, nothing aimed at minors. New field notes stay private until review. See a problem with a public note? Use Report on it; a note flagged by enough people is hidden automatically until it is checked.

Every community variant carries the same source and confidence labels as the records above. Nothing appears here unsourced, and no count is shown until it is real.