Logan Webb has one of MLB’s best changeups. He’s spreading it around the SF Giants’ clubhouse.

SCOTTSDALE, Ariz. — Sam Long pulled out his iPhone and opened one of his recent pictures.

It was a scatterplot from his most recent bullpen, with three distinct groupings of plots. There was a cluster in one color at the very top, and another at the very bottom. The third group, sitting barely adjacent to the top one, was what concerned Long this morning, though.

Each cluster of data points represented one of the offerings in Long’s arsenal, and each dot represented the movement on each of his pitches from the session. Up top, his fastball, with no vertical drop. Down low, his curve, with a lot. And way, way too close to his fastball was his changeup. It had too much helium.

“They sat me down and showed me some numbers,” Long said, “if I could get a little more depth on (the changeup) it would be even more effective.”

Enter: Logan Webb.

The owner of one of the game’s best changeups, Webb, you might think, would be hesitant about sharing trade secrets.

Not so.

“It just wasn’t moving how I wanted it to. I didn’t know why. I was throwing the grip they wanted me to and it just wasn’t moving as much,” Long recalled. “And (Webb) just showed me what worked for him. It wasn’t anything crazy, just a little short quick tip.”

And Long isn’t the only one.

“There’s a bunch of guys messing with it,” Webb said.

Taking after the veterans the came before him — Kevin Gausman, Jeff Samardzija and Johnny Cueto, in particular — Webb has embraced the sharing of knowledge and collaboration among the starting staff. It was that group before Webb that initiated the process of other starters watching each others’ throwing sessions between starts. That practice continues, and this spring, Webb has spread the good word to a number of inquisitive teammates.

Long. Jakob Junis. Sean Hjelle.

Even veteran reliever Scott Alexander has picked the 26-year-old Webb’s mind in this first week of camp.

“We get the pitch reports when we throw our bullpens. They’ll show the movement on the pitch, and the movement on his changeup was big,” Alexander said. “So I was just asking him what he did to get the depth on his pitch.”

Turns out, Alexander was already throwing his change in a similar way as Webb.

The others have made bigger adjustments.

But what, exactly, makes Webb’s change so effective? Batters hit a paltry .206 against the pitch last season, and it was worth minus-12 run value, according to Baseball Savant, making it the sixth-most effective change in the game.

“Just the way he holds it and the way his arm action works, he gets this spin where you can just see the top of the ball rotating and it has that depth to it,” Junis said. “That’s what we’re all trying to do. We’re all trying to emulate that.”

For the lucky few sitting behind home plate, and the unfortunate batter in the box, that depth is apparent. For the reader at home, the numbers behind it: Webb’s change in 2022 averaged 42 inches of vertical drop, or 18% more than league average, once again ranking among the top 10 in MLB.

What makes it even more unique is that the movement is almost straight down: the bottom falls out.

The key? Allow Long to explain.

“Just with the grip, usually every other pitch you’re throwing is coming off of your fingertips. The changeup, you’re trying to kill the speed, so you put it a little more toward the palm,” Long said. “It just takes a little bit more feel. So for him, he says spreading out his fingers has always helped kill the spin on the ball and kill speed.”

How Webb achieves this effect can be traced back to Gausman, and then even further to a since retired former minor league teammate.

The grip Webb uses today he picked up from Mac Marshall, a fourth-round draft pick in 2015 with whom Webb spent parts of three seasons at three different levels. Marshall, who remains good friends with Webb, retired in 2021 after making it as far as Double-A, but a piece of him lives on every fifth day.

Of course it was Gausman, who doesn’t throw a changeup but is a master of the splitter, who suggested to Webb splitting his fingers.

“That’s all I was telling Sam. When you throw it, just split your fingers a little bit more,” Webb said. “That might add a little bit of that friction that you want to make it go down. … That’s all I’m really trying to do: see how far it can go down.”

The answer: a lot.

And the relationship isn’t one-sided.

When Webb was searching for his slider last season, he sought out Junis, who threw his more often than any other starter in the majors last year.

Which makes it all the easier for someone like Hjelle, who is fighting for a roster spot and said he has fought to find a changeup that felt good since being drafted. After consulting Webb during one of his stints with San Francisco last season, Hjelle found the grip that stuck.

“That shows you how long I’ve been trying to figure something out,” Hjelle said. “It’s just the environment of this clubhouse, guys just helping each other out. Especially for me and where I’m at, my role is somewhat uncertain. I’m on the fence. It could go either way, right? I’m technically at that point gunning for somebody’s job. But to have guys around here who are still willing to give advice and help you out, it’s what’s going to make us good this year.”