Skip to content

Classic success: The Mariners' approach to pitching won't ever go out of style

Julian Catalfo / theScore

Amazon founder Jeff Bezos once said that he's often asked what's going to change in the next 10 years. "I almost never get the question: 'What's not going to change in the next 10 years?'  he said. "And I submit to you that that second question is actually the more important of the two."

Things that never change are important because you can put so much confidence into knowing how they'll shape the future. Bezos said it's impossible to imagine a future where Amazon customers don't want low prices and fast shipping - so he can put enormous investment into those things. The same philosophy works in almost all areas of life.

- From the book "Same as Ever" by Morgan Housel

PEORIA, Ariz. - Over the last decade, there's been more change in Major League Baseball than in the preceding half-century. The amount of new data, new technology, and new ways of thinking about training skills have changed the game profoundly.

Each spring we seem to hear about a new pitch proliferating throughout the game, hitters making swing changes, and new tech and data aiding them. Even the rules changed last year in response to how quickly the game was evolving; MLB added a pitch clock, shift bans, and larger bases.

There is always so much focus on what is new.

But perhaps what is more important in team building and development is knowing what never changes.

In considering what to do next, what to build next, it's of great help in business - and in baseball - to know what will remain timeless.

When Seattle Mariners general manager Jerry Dipoto was asked about what remains the same in baseball, he only needed a moment to respond.

"Fastball quality and the strike zone," Dipoto said. "I don't think that will ever change, unless they fundamentally change baseball."

It just so happens the Mariners are capitalizing on those timeless principles.

Alika Jenner / Getty Images

Last season, the Mariners finished with the second-highest first-pitch strike percentage (64.5%) since the stat was first tracked in 2002. They trailed only the 2005 Minnesota Twins (64.7%).

This season, through play Monday, the Mariners are bettering that rate (65.9%), again leading the majors. They also lead in strike percentage (66.4%), just as they did last year (66.1%, while the MLB average was 63.9%).

Since the start of the 2023 campaign, the Mariners lead the majors in FanGraphs' fastball run value.

A mostly homegrown Mariners rotation enjoys excellent command and fastballs, and it ranks fourth in pitching WAR since the start of last season. Their pitchers are the key reason the club is in the mix in the AL West despite run-scoring woes. What can we learn from this timeless group?


Let's first consider the foundational principle of throwing strikes: Everyone preaches it, but not every team can execute it.

Harping on the concept starts early with the Mariners. Every February, the Mariners make a similar presentation to prospects who join the system from the most recent draft and signing classes.

In a meeting room on their Peoria, Arizona, campus, they make a color-coded presentation to the aspiring group of arms.

"Do you remember the color-coded (strike zone) in Ted Williams' book, 'The Science of Hitting?'" Dipoto asked. "We take that image, pin it, and run through the counts."

Ted Williams book cover

Major League Baseball's Statcast can spit out similar heat maps for pitchers and hitters, and every team's analytics department can do the same.

There's a reason they're popular. The visual effect is striking.

As we wrote last week, the difference in the outcome of a plate appearance that starts 1-0 versus 0-1 is about 200 points of OPS. That's roughly true in every season dating back to 1988 when pitch-level data was first recorded. It's something of a baseball law. More than half of the battle is getting ahead in the count.

"Our overwhelming message to our players isn't to throw it harder, isn't to ride (a fastball) higher, it isn't to sweep it more," Dipoto said. "Our first, second, and third message is that it's about the strike zone."

The Mariners preach throwing strikes and prize it.

They made George Kirby a first-rounder in 2019 out of Elon, a small Division I school in North Carolina, where he had walked just six batters across 88 innings in his junior season.

Last season, Kirby became one of three qualified pitchers in the last decade to walk fewer than one batter per nine innings (0.90), and he's doing it again this season (0.94) as MLB's most accurate pitcher.

Steph Chambers / Getty Images

Of course, it's one thing to know the benefits of pitching in the zone - it's quite another to do it. Not only is command a skill, but living in the zone also requires confidence. That confidence is tied to one pitch: the fastball.

Consider how often different pitch types are being thrown inside the strike zone this season.

Only fastballs are thrown within the zone at least half the time. That is true of last season and seasons before that. It's another baseball constant.

If one is going to live in the zone, they need a quality fastball.


Part of the Mariners' pre-draft evaluation process involves sending the names of every high school and college pitching prospect who caught their scouts' eyes to Trent Blank, the club's pitching strategist.

Blank analyzes data and video, adding another filter through which to view pitchers.

Blank and the Mariners place significant value on a pitcher's fastball. In the age of modern pitch design, where the tech-and-video feedback loop helps pitchers expand or improve their arsenals, the fastball remains difficult to improve.

"It's tough to get a fastball to grade out really well if you are not naturally built for it," Mariners pitcher Logan Gilbert said. "But the offspeed pitches can improve. … Everyone can throw a curveball or slider."

While pitchers can add velocity through modern training, they cannot add spin to their fastballs. The shape is difficult to change.

Mariners pitcher Bryce Miller cannot explain how to replicate his high-spin fastball.

"You can either spin it, or you can't," he said.

Bryan Woo wasn't a highly sought-after prospect coming out of Cal Poly in 2021. He had posted a 6.11 ERA and 1.46 WHIP in his junior year and required Tommy John surgery.

But what Dipoto said jumped out to Blank was the amount of rise effect Woo could generate from a lower arm slot. It's a trait some of the best fastballs in MLB share.

"We always throw hundreds of names at (Blank)," Dipoto said. "I think Trent's response in Bryan's draft year was, 'If I had the first pick, this is who I would take.'"

The assessment sent Woo soaring up the Mariners' draft board.

On draft day, after playing something of a game of chicken with the 29 other clubs, the Mariners selected Woo in the sixth round. Seattle signed him for a slightly over-slot bonus ($318,000) to persuade him to finish his Tommy John rehab with the club.

Aaron Doster / Getty Images

It's turned out to be a steal. Woo was impressive as a rookie last year, posting a 25% strikeout rate with a 4.21 ERA, and is expected to soon return to the rotation from a rehab assignment.

"Woo didn't have a very successful collegiate career from a productivity standpoint. But the data, the pitch traits jumped off the page," Dipoto said. "His fastball is just a special pitch. He's got one of those heaters where he can tell you it's coming and it rushes on you. Even when you are playing catch with him, or standing there next to the guy who is playing catch with him, the way they jerk their glove. The ball has an unusual ride from a little bit of a lower slot."

Miller is a similar case. As a junior at Texas A&M, he moved to the rotation from the bullpen. While it started well for the lithe right-hander, he struggled in the second half of the season.

"I think after his first five or six starts we were really interested … particularly the ride on his fastball and how playable it was," Dipoto said. "We were starting to talk about him (for early-round consideration). But largely due to the fact he was never really stretched out innings-wise … he kind of faded in the second half of that draft year and it benefited us, falling a pick to where it was a huge value to us.

"From an evaluation standpoint, if I'm being honest, we thought we would probably wind up getting an impact reliever. What we didn't count on with Bryce was just how much aptitude he has."

The Mariners selected Miller in the fourth round in 2021 and signed him for $400,000. In his sophomore MLB campaign, he's posted a 2.61 ERA and 0.92 WHIP. From a run-value perspective, Miller possesses the third-most valuable fastball in the majors this season.

Even pitches in the heart of the plate can be difficult to square.

And because his fastball was so good, Miller began trusting it more in the zone as a professional.

Steph Chambers / Getty Images

His command improved as a professional from walking 4.6 batters per nine innings in college to 2.8 as a minor leaguer to just over 2.0 batters per nine in the majors.

"We have (pitch quality) scores and all that stuff in the minor league that shows how well your stuff measures up to the MLB average," Miller said. "And a lot of my pitches were above the MLB average. They were like, 'Why would you be afraid to attack the middle when you know your stuff is above the major-league average?' It definitely added confidence. Once I got (to the majors), just knowing how good the stuff was, it didn't matter who was in the box."

He added, "It really changed how I pitched, how I was able to attack hitters."

Luis Castillo, the veteran of Seattle's rotation who was acquired from the Cincinnati Reds at the 2022 trade deadline, owns another excellent fastball. Castillo's heater was the fourth-best in the majors last year by run value.

"The best pitchers in any generation since baseball was born were pitchers who had a quality fastball," Dipoto said. "It could have been 100 mph or 92 with a back-door sink. It could have been overwhelming power like you see a lot of with today's guys, or it could have been with precision and ball action like Greg Maddux. But the fastball quality is the key. That will never change."


When a pitcher possesses a great fastball, he and his organization can plan to build off it in this age of designer breaking balls. It offers a clear way to improve.

Miller went to work on a split-fingered pitch last offseason at Texas A&M with the school's pitching coach, Max Weiner, who previously worked for the Mariners.

Seattle and Miller agreed he needed something softer to complement his pitch mix of mostly hard stuff. The problem was he'd always struggled to throw a traditional changeup.

"I already cut the fastball, so it's just hard to get inside a changeup without dropping the slot and tipping," Miller said.

Said Dipoto, "He is curious, as much so as any other guy we've had. And we have a curious group. He works with our pitching strategists and coaches … as nonstop as anyone we have. If you talk to Bryce, you get the 'Aww shucks' version. But he's really sharp. He puts together plans better than most."

Said Miller, "I watched Logan and George throw (a splitter) last year and I was like, 'I will try that.'"

Gilbert had a similar issue in being unable to throw a traditional changeup because of his arm slot and grip. So prior to last season, he went to Driveline, an independent training facility in suburban Seattle, to design a new pitch.

"It was quick," Gilbert said. "I was there for one pitch-design session, a 30-pitch bullpen. … It's really guess-and-check. A lot of Trackman (pitch metrics) and Edgertronic (high-speed camera)."

Brandon Sloter / Getty Images

Gilbert now possesses five above-average pitches.

Thus far, Miller's split-finger looks to be an excellent addition to his fastball and slider. The pitch averages 40 inches of drop from release - 12% above the MLB average. He killed the pitch's spin, turning it into a diving, knuckling weapon.

"I am throwing it with not much spin, so it has a mind of its own," Miller said. "It's come a long way, but I still have a long way to go."

Woo is next in line to expand his arsenal, Dipoto says. He already enjoys the key foundational elements: a rare fastball with command of it.

We don't know the next en vogue pitch or training practice in baseball, but we do know what remains the same. The Mariners are starting with that foundation and building from there.

"That will never change," Dipoto said. "If you have that, you can pitch forever."

Travis Sawchik is theScore's senior baseball writer.

Daily Newsletter

Get the latest trending sports news daily in your inbox