'It's 100 or die': How throwing 100 mph went from a novelty to the norm in MLB

The allure of 100 is mostly about the extra digit and humans' adoration of round numbers. Ask a hitter to tell the difference between 99 mph and 100 mph, and he can't. Nonetheless, it's a badge of honor for pitchers. Tall ones do it. (At 6-foot-8, Marlins right-hander Eury Perez has a 14 at 100-plus this year). Short ones do it. (The Cubs' 5-foot-11 closer, Daniel Palencia, has exceeded 100 seven times.) Starters and relievers do it, sometimes with the same frequency. (The MLB leaders this year: Milwaukee ace Jacob Misiorowski with 70 and unhittable San Diego closer Mason Miller with 60.)

And, in the end, as Klein puts it: "Yeah, it's fun to throw hard."

A quarter century ago, a right-hander named Colt Griffin became the first high school pitcher to throw 100 -- and was drafted by Kansas City with the No. 9 pick even though he couldn't throw strikes. He retired four years later. Now, 100 is so common -- in the minor leagues, college, even high school -- that the best pitcher in the world worries it's being taken for granted.

"Throwing a baseball 100 miles an hour -- I don't think fans understand how hard that is to do," said Detroit ace Tarik Skubal, winner of two consecutive American League Cy Young Awards. "It looks easy on TV when big leaguers are doing it. It seems like everyone's got multiple guys that throw 100. But I do think it's not as easy as -- I know it's not as easy as what it looks like."

More than a century ago, Walter Johnson defined fastball velocity; he might have touched 100. In 1940, Bob Feller famously threw his fastball harder than a speeding police motorcycle, clocking in at 98.6 mph -- which, considering he was in street clothes and throwing on flat ground in Chicago, suggests he, too, hit 100. Even after Nolan Ryan threw 100 with regularity, there remained a mythic quality to the number, as if it were the domain only of those with arms kissed by fortune.

It turns out, 100 was lurking within all these years. The game just needed to find it.

"It seems like everyone throws 100," Dodgers manager Dave Roberts said. "And every hitter knows it."

IN HIS FIRST start at Double-A on June 21, 2005, Justin Verlander, who went on to throw hundreds of triple-digit pitches in the big leagues, came out consistently pumping 100 and 101 mph fastballs. After he struck out the first seven New Hampshire Fisher Cats hitters he faced, the radar gun in the stadium stopped working.

"I don't think they wanted to see their guys seeing 00 and 01 when they were walking up to the plate," said Don Kelly, now the Pirates' manager but who was an infielder behind Verlander that day.

Whether it was a malfunction or an active choice to shut it off, Kelly doesn't know. But it speaks to the power of 100 and its ability to infiltrate the psyche of a hitter.

"It's not the same just because it's not as rare," Kelly said. "I still don't know how these guys hit it. I think it's still difficult to hit when it's up to that speed."

Which is why fastballs at 100-plus mph continue to flummox hitters. In plate appearances that have ended on such pitches this season, hitters are slashing .165/.248/.187. Last year wasn't much better: .193/.268/.283. Compare that with fastballs at 98 mph (.237/.326/.341), 95 mph (.267/.355/.432) and 90 mph (.281/.365/.479), and it's easy to understand why the industry is pursuing 100.

The most significant change came in the past half a decade, when a proliferation of pitching labs popped up around the country, equipped with technology that makes the humble radar gun look like a Commodore 64. Modeled after the labs that have become a necessity for major league teams across the game, all it took was a Trackman unit and an ultra-high-speed camera for trainers to optimize a player's velocity. The offseason is something of a misnomer because the majority of professional pitchers today spend their winter at work, often in search of another mile an hour or two to bring with them to spring training in February.

A pitcher showing up to camp, suddenly popping 100 mph, is not just within the realm of possibility; it's a golden ticket, as roster decisions often run parallel with a player's fastball velocity. With rare exception, throwing 100 eventually will guarantee a big league roster spot. It doesn't need to be for consistent strikes. It doesn't need to be particularly effective. Front offices hand immature -- but live -- arms to coaching staffs and task them with finding the consistency to help them stick.

The Colorado Rockies, forever in search of something that helps mitigate the thin air that has turned Coors Field into a hitting playground for three decades, have embraced velocity. Their bullpen owns the highest average fastball velocity in the major leagues this year at 96.6 mph. Between Chase Dollander and Victor Vodnik, they've got a pair of relief pitchers in the 100 mph club, and Juan Mejia, Jaden Hill and Antonio Senzatela -- all averaging over 97 mph on their fastballs -- could join them this season.

Developing 100 mph arms isn't nearly the chore it once was. Players happily forgot incremental velocity gains for leaps. After signing with the Oakland A's as a 20-year-old out of Venezuela, Palencia, who was throwing in the low 90s, used his signing bonus to improve his nutrition and workout equipment.

"By January, I was hitting 98," he said. "Then in spring, my first outing, I hit 100."

Teams also rely on a tried-and-true method that preceded the velocity revolution: the starter-to-reliever bump. Pirates left-hander Mason Montgomery spent three years as a starting pitcher at Texas Tech with a fastball in the 90 to 95 mph range. His fastball stayed there in the minor leagues with the Tampa Bay Rays, too, until they moved him into the bullpen in August 2024. In his first appearance, he hit 98, his hardest pitch of the season to that point, and a week later, he was sitting there.

The freedom of pitching in relief -- knowing that for one inning, a pitcher can air it out with no need to ration his arm -- can unlock another level.

"I always thought I'm going max effort or relatively max effort," Montgomery said. "But I think maybe in the back of my mind I was also thinking, yeah, I got to go five, six, seven innings. So, that probably plays a part."

Said Palencia: "I was a starter. As a starter, they say save the bullets. As a reliever, I'm just trying to go."

The most telling cases -- and the ones most unique to the past five years -- are those such as Schlittler. In 2023, his first season after being chosen in the seventh round of the 2022 draft out of Northeastern, Schlittler's tracked fastballs averaged 90 mph. Working in a Yankees farm system that is among the best at extracting velocity, he gained nearly 5 mph on his average fastball in 2024. The next season brought another 2 mph, and he topped out at 99.3 mph.

Then came his major league debut, July 9, against the Seattle Mariners. On the 16th pitch of his major league career, Schlittler threw a 100 mph fastball. And in the time since, his 2.85 ERA ranks eighth in MLB, and his 97.8 mph average fastball velocity is third.

"I know a lot of dudes that throw hard in this league that get lit up," Schlittler said. "So, velo isn't always the most successful piece. But it definitely helps."

EARLIER THIS SPRING, a video circulated of a 16-year-old from suburban Philadelphia named Cole Kuhn throwing a fastball from a low arm slot that a Trackman clocked at 101.7 mph. As a freshman two years ago, Kuhn couldn't make the JV team at his high school. Now a junior, he's not on the St. Joseph Preparatory School's team, instead sitting out the spring season to rest his arm and prepare for a summer in which major league teams will scout him in anticipation of the 2027 draft.

Kuhn is an archetypal modern baseball story, the product of targeted training that aims to squeeze every last mile per hour out of a player's body. He is also not alone. Striker Pence, the 16-year-old nephew of four-time All-Star Hunter Pence, threw 10 pitches at 100 mph in one showcase outing this summer -- and followed that by touching 101 four times at a wood bat tournament in October. He is a sophomore at Santiago High in Southern California, a 6-foot-6 hurler who, with his long, blond hair, is reminiscent of prime Noah Syndergaard.

They're not the only prep players to reach triple digits this year, either. Four high school seniors being actively scouted by major league teams -- 6-foot-9 left-hander Brody Bumila, 6-foot-8 right-hander Savion Sims, 6-foot-6 right-hander Coleman Borthwick and 6-foot-5 right-hander Ethan Wachsmann -- have hit 100 this year, according to ESPN's Kiley McDaniel. At least another half a dozen have topped out at 99 mph.

Every week, it seems, a new college player hits 100. Mississippi State freshman Jack Bauer, who threw 103 as an Illinois prep in 2025, threw a 102.4 mph pitch last week. UC Santa Barbara's Jackson Flora, regarded as the top college pitcher in this year's draft, popped 100 earlier this season.

And that's to say nothing of the arm talent in the minor leagues. Though not every minor league pitch is tracked by Statcast, last year, 70 minor leaguers threw a fastball 100-plus, according to MLB's data. This season, according to Statcast, 27 pitchers have already exceeded 100.

In the same way Chandler saw Fernández and wanted to be like him, young pitchers today have examples aplenty to mimic. In 2015, 49 pitchers threw 1,389 fastballs at 100-plus mph (with 503 coming from Aroldis Chapman). In 2025, the aforementioned 82 heat-seekers fired 3,701 triple-digit pitches.

There have been 428 pitches this season at 100-plus mph -- 37 more than last year at this juncture of the season -- and last year only 22 pitchers threw them, a baker's dozen fewer than this year. Chandler has more of those pitches than just three other players. Ten of his 36 have been at 100 on the dot. Two have crept over 101. After speaking 100 into existence, he now gets to live with its spoils.

"Obviously, it looks cool," Chandler said. "If you throw strikes with 100, it's cool. If you command 100, it's even cooler. That's the goal, put your body in a good spot every week to go out there and throw bullets and throw them where you want to, and that's it.

"It takes a village to do anything great, and I think each individual guy has their own village that they use and, yeah, I think you're blessed with ability, but then you got to work for it. I've worked pretty hard the last handful of years to put myself in this position and do cool things."

ESPN's Jorge Castillo, Alden Gonzalez and Jesse Rogers contributed to this report.