The short answer: build new pitches in the offseason, and keep in-season changes small. That rule sounds obvious, yet plenty of pitchers break it every spring, usually because a hot bullpen convinced them a pitch was ready. Timing decides whether a new grip becomes a weapon or a habit you abandon by June. This guide covers why the offseason works, how pitch design fits into your workload, what each age group should actually attempt, and how to structure the weeks so the pitch survives contact with real hitters.
Why big pitch changes belong in the offseason
Pitch design is a planned block of throwing where you change one thing (a grip, a seam orientation, finger pressure or a cue), watch what the ball does, and keep only the changes that repeat and solve a real problem [1][2]. Every part of that process needs room to fail. In season, a failed experiment can cost you a start and the trust of the coach who sets the lineup.
The professional examples cluster in winter for that reason. Ben Brown of the Cubs built his new two-seamer over the 2025 to 2026 offseason after getting hit hard with his four-seamer, learning a grip from Clay Holmes at a training facility near Nashville [3]. Driveline's research group describes arsenal construction as an offseason project in its Saberseminar 2025 presentation [4]. Ben Brewster of Tread Athletics gives the same advice from the coaching side: big changes go in the early offseason, and in season he limits himself to "set and forget" setup tweaks [5].
There is also a skill reason. Driveline coaches point out that changing something like fastball spin efficiency in a closed bullpen is far easier than holding that change under game stress [6]. A pitch needs weeks of repetition in calm conditions before it can hold up when a hitter is in the box and the count is 2-1.
What you can change during the season
In-season pitch work is real, it just operates at a smaller scale. Good in-season adjustments include:
- Usage by hitter side and count. Throwing an existing pitch more often to the hitters it beats is often the fastest improvement available [2].
- Targets. If a pitch keeps finishing in the same wrong spot, moving the starting target can fix it without touching the grip.
- Small grip pressure tweaks. A little more pressure on one finger, tested in a normal bullpen, is a manageable change.
- Rubber position. Some coaches treat a move on the rubber as a setup tweak, though it can change the angles of every pitch, so test it carefully against both batter sides [2].
Brand-new pitch types, seam orientation projects and arm slot changes are better saved for the winter.
Pitch design is a workload decision
Here is the part most pitchers skip. New grips are thrown with real intent, often off a mound, and they disrupt grooved movement patterns. That makes pitch design a workload event as well as skill work [1]. A pitcher who adds forty experimental breaking balls a week on top of a full throwing program has quietly raised his workload, even if every throw felt easy.
Practical rules that hold up well:
- Count pitch design throws inside your plan. They replace planned throws on that day; they do not sit on top of them [2].
- Avoid stacking it on a velocity block. Two high-intent projects at once make it hard to tell which one caused soreness or a dip in command [1].
- Watch for spikes. A sudden jump in high-intent throws is the pattern to avoid.
- Use the lowest intensity that keeps the delivery clean. A Driveline trainer describes pitch design as needing plenty of mound throws at the minimum intensity that still keeps mechanics intact [7].
Premier Pitching suggests starting pitch design only after the acute:chronic workload ratio has sat around 0.8 to 1.3 for two to four weeks [1]. Treat that number as a coaching heuristic. A methods paper by Impellizzeri and colleagues concluded there is no evidence supporting the ratio for training recommendations aimed at reducing injury risk, partly because of statistical artifacts in how it is calculated [8]. A steady, gradual trend in your throwing volume is a sensible goal; a specific ratio has never been validated as clearance to throw.
Track the experiment
Log every grip change in Pitch Lab
Pitch AI's Pitch Lab logs your velo, IVB, spin, axis and release for each pitch, plots your arsenal on a movement chart and records every grip change, so an offseason pitch design block leaves a paper trail you can actually compare.
Match the project to the pitcher's age and level
Premier Pitching's developmental framework is a useful map [1]:
| Stage | Pitch design focus |
|---|---|
| Youth through early high school | A repeatable release, fastball proficiency and throwing strikes. Limited pitch design. |
| Late high school and college | The most practical entry point. Change one thing at a time, and stabilize the fastball first. |
| Advanced college and pro | Full design work, seam orientation and tunneling strategy. |
Brian Bannister, who has run pitch design for Major League organizations, makes a similar point about young players: even a decent changeup or breaking ball puts a youth pitcher far ahead of his peers, so simplicity wins [9]. He will sometimes build a young pitcher's arsenal around whatever spin the hand produces naturally, even if that means two breaking balls and no changeup. For youth pitchers, follow age-appropriate pitch counts and rest days from MLB Pitch Smart before thinking about new grips [10].
Split the work: shape days and execution days
Once mound work starts in the offseason, separate two kinds of sessions [1]:
- Shape days are low volume with lots of feedback. You change one variable, watch the ball, compare it with your old version, and stop when the delivery or the hand gets tired.
- Execution days look like a game. Sequences, locations and counts, with very little experimenting. This is where a promising shape learns to find the strike zone.
Keeping them apart protects both. Experimenting during a game-like bullpen muddies your command practice, and running sequences on a shape day hides whether the grip is doing anything.
A sample offseason timeline
Treat this as an example structure to adapt. Your calendar depends on when your season ends and starts.
| Window | Pitch design job | Notes |
|---|---|---|
| After post-season rest | Write the problem sentence and audit last season | No new throws yet. Look at which hitters and counts hurt you. |
| Throwing ramp-up | Grip exploration during catch play and early flat-ground work | Low intent. Photograph grips and keep notes. |
| Early mound work | Shape days: one variable per block, old versus new | Count every throw. Retest promising grips on another day. |
| Late offseason | Execution days: sequences, targets, live hitters | Hitter exposure is the real test. |
| In season | Usage, targets, small pressure tweaks | Save new pitch types for next winter. |
How long should the mound phase run? Bannister describes a typical new-pitch block as about four weeks: grip first, then finger pressure and cues, then fitting the pitch into the arsenal [9]. Fastball variants such as a two-seamer or cutter usually come fastest, which makes them a smart first project [11]. Other pitches take longer. Brown started a kick change in mid-2025 and still called it a work in progress the following February [3].
Start with a problem, then pick the pitch
Before you touch a grip, write one sentence: against these hitters, in these counts, I need a pitch that does this [2]. Getting left-handed hitters out and stealing a called strike when behind are real problems. "I want a sweeper because everyone has one" is a trend.
Driveline's Saberseminar group lists four legitimate reasons to add a pitch: more whiffs or weak contact (stuff), a pitch you can locate (command), an early-out pitch that produces soft contact, and arsenal effects where the new pitch makes the others better [4]. If your reason does not fit one of those, the offseason might be better spent on velocity and on commanding what you already throw.
Once you have the problem sentence, the rest of this series covers how to tell if a new pitch is actually good and how to run pitch design without a tracking device. For the step-by-step process, see our pitch design workflow, and for how throwing volume adds up across a week, read workload and arm care for pitchers.
What to do this week
- If you are in season, pick one existing pitch and look at where it works best by hitter side. Adjust usage before adding anything.
- If your season just ended, write your problem sentence now while last year's at-bats are fresh.
- If you are in the offseason ramp-up, choose one candidate pitch, photograph the grip, and schedule your first shape day inside your planned throwing volume.
- Whatever the season, log the throws. A plan you cannot see is a plan you cannot adjust.
Frequently asked questions
Can you learn a new pitch during the season?
You can start one, but it is the hardest time to do it well. In-season work is best limited to usage, targets and small grip pressure tweaks. Coaches at Driveline and Tread both place big changes in the offseason, when there are no games to protect and time to build feel.
How long does it take to learn a new pitch?
Brian Bannister describes a typical new-pitch block of about four weeks: grip first, then finger pressure and cues, then fitting the pitch into the arsenal. Fastball variants usually come fastest. Some pitches take much longer; Ben Brown was still calling his kick change a work in progress months after starting it.
At what age should a pitcher start pitch design?
Premier Pitching places the practical starting point in late high school and college. Younger pitchers do better focusing on throwing strikes, a good fastball and one secondary that suits their hand, while following age-appropriate pitch count and rest guidelines such as MLB Pitch Smart.
Do pitch design throws count toward workload?
Yes. New grips are usually thrown with real intent, so count them inside your throwing plan, avoid stacking them on top of a velocity block, and avoid sudden spikes in high-intent throws. No acute:chronic workload ratio has been validated as a safe zone for starting.
Plan the block
Build your next pitch inside your throwing plan
Pitch AI logs every throwing session and builds workload progressively, so new-pitch throws count toward the plan instead of piling on top of it. Log your pitch metrics and design your arsenal in Pitch Lab, and let the daily Wellness Check-In (arm freshness, soreness, pain) pull volume back on the days your arm says so.
References
- Premier Pitching Performance Team (2026). The Pitch Design Phase in Baseball: Developmental Fit, Workload-Informed Timing, Biomechanical Determinants of Effectiveness, and Evidence-Based Evaluation Thresholds. Premier Pitching Chronicles. https://premierpitching.com/blogs/premier-pitching-chronicles/the-pitch-design-phase-in-baseball-developmental-fit-workload-informed-timing-biomechanical-determinants-of-effectiveness-and-evidence-based-evaluation-thresholds
- Pitch AI (2026). Pitch Design Playbook, with Pitch Trial Log and Pitch Decision Log templates. Internal coaching synthesis, September 2026.
- Laurila D (2026). Ben Brown Pitch-Designed a Sinker Over the Offseason. FanGraphs, February 27, 2026. https://blogs.fangraphs.com/ben-brown-pitch-designed-a-sinker-over-the-offseason/
- Hejka J, Lambert J, Ramilo M; Driveline Baseball (2025). Projecting Pitch Design, Saberseminar 2025 presentation. YouTube, December 31, 2025. https://youtu.be/HeBvjYrU_vk
- Tread Athletics (Brewster B) (2026). Throw Harder By Changing Your Pitching Mechanics [The Right Way]. YouTube, September 24, 2026. https://youtu.be/_EilR25ydwY
- Driveline Baseball (Langin C) (2022). How to Throw a Four Seam Fastball. YouTube, May 26, 2022. https://youtu.be/YQkUrg4obaA
- Driveline Baseball (2026). What 1,000 Bullpen Days Told Us About Pitch Counts. YouTube, October 10, 2026. https://youtu.be/5OZjHuvBtiY
- Impellizzeri FM, Tenan MS, Kempton T, Novak A, Coutts AJ (2020). Acute:chronic workload ratio: conceptual issues and fundamental pitfalls. International Journal of Sports Physiology and Performance, 15(6), 907-913. doi:10.1123/ijspp.2019-0864 https://doi.org/10.1123/ijspp.2019-0864
- Tread Athletics (2022). Brian Bannister: Mastering Pitch Design (podcast). YouTube, December 22, 2022. https://youtu.be/E0yoPt42A5Q
- MLB and USA Baseball. Pitch Smart: Pitching Guidelines. https://www.mlb.com/pitch-smart/pitching-guidelines
- Sawchik T (2025). How many fastballs should a pitcher have on the menu? Driveline Baseball, November 25, 2025. https://www.drivelinebaseball.com/2025/11/how-many-fastballs-should-a-pitcher-have-on-the-menu/