Keep the ball out in the fingers.
A light two-seam split, the ball held shallow, not wedged deep between the fingers.
A fastball that sinks like a splitter.
Splinker
A light two-seam split, fired near fastball velocity. It looks like the 98 mph four-seam out of the hand, then dives arm-side and down. A pitch only a handful of arms throw.
Specimen 06
seam-informed schematic
Sourced, not corrected
01Grip Lab
View
Hand
Drag to inspect, or use the View buttons
The hybrid / 06
Splinker
It leaves the hand like a 98 mph fastball, then sinks and runs like a splitter.
Ball depth
Out in the fingers
Spacing
Wide spacing
Thumb
Thumb supports underneath, centered between the lightly split fingers.
Release feel
Fastball arm and velocity; the light split and index pressure add the sink and tail.
A light two-seam split, the ball held shallow, not wedged deep between the fingers.
Palm gap cue
- Index pad / Adds the arm-side tail with extra pressureLightly split on a two-seam orientation. Split, not wedged; press to tail.
- Middle pad / The other half of the light splitSplit off the index, held shallow. Shallow split, not deep.
- Thumb / Balances the ball under the split fingersUnder smooth leather, centered. Centered underneath.
See it live / via @PitchingNinja
The grip is the cause. This is the effect, the same pitch shot in a real bullpen. Sourced, not corrected.
- 1Split your index and middle fingers wide across a two-seam orientation.
- 2Hold the ball shallow between them, not wedged deep like a splitter.
- 3Add a little extra pressure with your index finger to pull the arm-side tail.
- 4Throw it with fastball arm speed; the low spin gives you the late dive.
Throw it like the fastball. The light split and a little index pressure add the dive.
The sourced grip, in full
A light two-seam split: the index and middle fingers split wide across a two-seam orientation with the ball held shallow, not wedged deep like a traditional splitter. Skenes adds index-finger pressure for the arm-side tail.
Reputable analysisMLB.com, Explaining Skenes' expanding arsenal (Mike Petriello)/ 2025
Grip mechanics are reporter paraphrase (MLB.com and Yahoo Sports on Skenes demonstrating it), not the pitcher's verbatim words.
Skenes has said the grip itself did not change when the modern, sharper version emerged; his release and the feel at release changed, which he stumbled onto on one random throw and then repeated.
Reputable analysisFOX Sports, Paul Skenes and his splinker at the All-Star Game/ 2024
Paraphrased from Skenes' FOX Sports account; his direct quote is in the chapter's voice.
Duran reached his version by widening a sinker grip; the pitch surfaced by accident in a 2018 bullpen, then he kept it. Both arms hold it to look like the four-seam out of the hand.
Reputable analysisMLB.com, Meet the 'splinker' pitch (Jhoan Duran, Do-Hyoung Park)/ 2022
From MLB.com's feature on Duran, who first popularized the pitch.
Grip geometry is schematic. Skenes shows a clearly split grip on a two-seam orientation; the index-finger-pressure detail is reporter paraphrase, not a verbatim quote.
02Release Room
Translate the hold into a release.
Grip shape only matters if the release makes sense. This room keeps the player reading pressure, thumb support, and ball depth before movement numbers show up.
Throw it like the fastball. The light split and a little index pressure add the dive.
index finger owns the shape.
Adds the arm-side tail with extra pressure
Release is a feel, not a formula.
Fastball arm and velocity; the light split and index pressure add the sink and tail.
Film Room / watch a master
The schematic shows the release path. This is the release: Gibson walking through the delivery himself. Real hand, real ball, real finish, no model can fake it.
Thrown with fastball arm speed and near-fastball velocity. The low spin produces extra drop and arm-side run, and because it leaves the hand on nearly the same path as the four-seam, hitters cannot separate the rising fastball from the diving hybrid until it falls.
Reputable analysisMLB.com, A splinker? Skenes' hybrid pitch (debut, Alex Stumpf)/ 2024
Paraphrased from MLB.com's coverage of Skenes' debut splinker.
03Movement translation
A second fastball that falls off the table.
It tunnels off the four-seam, leaving the hand on nearly the same path at nearly the same speed. Then the low spin lets it dive down and toward the throwing arm, so the hitter has to guess which fastball is coming.
The measured movement, if you want it
It is a second fastball shape: near-fastball velocity off the same arm slot and release as the four-seam, then a late dive and arm-side run the four-seam never makes. The hitter has to choose between the rising pitch and the diving one out of the same hand.
Synthesized from MLB.com; the pitch tunnels off the four-seam, then separates.
Spin axis and force direction, drawn in render space
Spin rate
≈ About 1,750 rpm, far below the average MLB sinker at roughly 2,150 rpm. The low spin is exactly why it behaves like neither a true sinker nor a true splitter.approx
Per MLB.com's arsenal breakdown; not independently re-pulled from Savant.
Arm-side dive
In his MLB debut, Statcast logged 31.4 inches of vertical movement and 13.8 inches of horizontal movement, a profile nearly identical to Zack Wheeler's elite splitter (31.8 / 13.4) but roughly nine mph harder.
Total movement figures from MLB.com's debut coverage.
Velocity off the fastball
About 94 mph, roughly four mph under his four-seam (about 98 mph) and nearly eight mph above the average MLB splitter at 86.5 mph.
Spin axis
A low-spin, sinker-like axis with arm-side tilt, but the spin-based flight path stays similar to the four-seam fastball, so the two look alike out of the hand before the splinker dives.
Near-fastball velocity off the four-seam look, then a late dive and arm-side run.
“It’s not like any other sinker, and it’s not like any other splitter. It’s a hybrid pitch. ... Call it whatever you want.”
Paul Skenes to MLB.com, on the splinker resisting classification. He himself calls it a sinker.
02Master files
The verified baseline.
The few arms throwing it: the one who popularized it, the one who made it famous, and the closers chasing it. The visual is our own seam schematic. Every figure links to its source.
Master file · 01Verified · Attributed
Paul Skenes
Made the pitch famous. Discovered it by accident playing catch after the 2023 College World Series, then turned it into one of the most valuable pitches in baseball.
Velocity
~94 mph
Spin rate
~1,750 rpm
Run value since debut
+18 (top-five pitch in MLB)
Opponent average (first 6 starts)
.073 (3-for-41)
Master file · 02Verified · Attributed
Jhoan Duran
The arm who first popularized the splinker, discovering it in a 2018 bullpen after widening a sinker grip. The hardest version in the game.
Velocity
97.7 mph (tops 100)
Reputable analysisFanGraphs, Jhoan Duran and the One True Split-Finger Fastball/ 2025
2025; Statcast classifies it as a splitter.
Induced horizontal break
13.9 in (top-10 among splitters)
Reputable analysisFanGraphs, Jhoan Duran and the One True Split-Finger Fastball/ 2025
Master file · 03Verified · Attributed
Mason Miller
Added the splinker to a 100-plus mph fastball and a wipeout slider, unveiling it in a May 2024 game with extra horizontal ride.
First in-game velocity
Horizontal movement
15-18 in
Official dataMLB.com, Mason Miller adds a splinker/ 2024
Filed only when the bar is met. A real figure from the wrong tracking system, or a great arm whose signature pitch sits in a different category, gets left off rather than dressed up. The gap is the honesty.
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 keeps those experiments visible, labeled, and debated, 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 velocity. 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.
The living layer
Field notes open soon.
Soon you will log your own grip tweak, mark the ones you have tried, and flag anything off, anonymously or under a handle you keep. When the community layer opens, every note will carry a source and confidence label, a content filter will block abusive language, and any note can be flagged. A note hides automatically once enough people report it.
When they open, every community variant will carry the same source and confidence labels as the records above. Nothing appears here unsourced, and no count is shown until it is real.