Shortly after Christmas in 2019, Logan Webb got a call from Brian Bannister, the former major-league pitcher, who the San Francisco Giants had just hired to fill a new-age role titled “vice president of pitching development.” Bannister was tasked with working with Giants pitchers and coaches to build the best possible deliveries and pitches for all the arms in the system.

After some brief introductory small talk, Webb was quickly taken aback by the message.

“Maybe 45 seconds into the call, he’s talking about how I’m going to change arm slots,” Webb told theScore earlier this season. “Forty-five seconds in and you want me to switch everything I’ve done?”

Prior to hiring Bannister, Giants coaches were working with Webb on refining his four-seam fastball, his primary offering. They wanted him to pitch more effectively with it at the top of the zone, and also wanted him to add a cutter to play off it. (In the Statcast era, elevated four-seamers are an en vogue pitch designed to get swing and miss above uppercut swings.) That experiment was now over, and Bannister recommended Webb do something completely different.

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At the time, Webb was coming off his first partial season in the majors – a season of struggles. He was hit hard in his first 39 innings, posting a 5.22 ERA. As he digested Bannister’s message and plan, Webb became open to it.

The story of Webb’s ascension to the top of a major-league rotation, where the Giants need him to keep pitching well to try and jump back into the wild-card race, is a story about individualized development. The idea that there are one-size-fits-all organization philosophies in how or what to throw are over. The Giants build upon an individual’s strength. And what Webb did so naturally well after an adjustment has allowed him to ride the wave of one of baseball’s great breakthroughs in pitching science, one that in December 2019 even the Giants didn’t see coming.


A few weeks after the call, Webb reported to spring training and began working on the Giants’ plan for him.

“They literally told me to throw sidearm,” Webb said.

Bannister shared with Webb video of Chris Sale’s motion; Bannister was familiar with the lefty ace from his time in Boston. The goal was for Webb to throw nearer to Sale’s low arm slot. So in the sun-soaked Arizona bullpens, Webb started dropping down with little initial instruction other than to throw lower and find something that felt comfortable.

Watching over the project was then first-year pitching coach Andrew Bailey. Bailey and the Giants staff felt Webb should embrace his “unique” athletic movements and be more rotational than direct to home plate in his delivery.

Once a pitcher himself, Andrew Bailey helped Webb build a new throwing motion. Matt Brown / Getty Images Sport / Getty

“When I first came on, Logan was a prospect with some big-league time and he really didn’t understand himself as a mover, as a pitcher, what he was trying to do – and it’s a scary place,” Bailey told theScore. “You start to struggle, you get internally focused on some delivery stuff. You don’t have a foundation.”

Rather than burden Webb with too much information, Bailey focused on a few cues about timing and throwing motion.

Webb’s vertical release – how high a pitcher releases the ball above the ground – dropped from 5.58 feet in 2019 to an average of 4.99 feet over the last two seasons. Of 463 pitchers to qualify over those time periods, only A.J. Puk and Javy Guerra lowered their arm slots more.

The arm slot change was key because Webb was going to alter what he threw out of it.

Instead of four-seamers, Webb was to only throw two-seamers, which the Giants felt was a better pitch in terms of movement profile. While sinkers had fallen out of fashion with many pitchers, Webb was reminded: not too long ago, Jake Arrieta won a Cy Young Award with the Chicago Cubs by relying on a sinker-slider mix.

Even in long toss and in catch with teammates, Webb was to throw with only a two-seam grip – no four-seamers. That was the message from Bannister and Bailey. His right index finger and middle fingers were to go along with the seams, not run perpendicular to them. They were going to still try and miss bats, of course, but ground balls were great, too.

Webb had thrown two-seamers before in the minors, when his elbow started to hurt, but after Tommy John surgery he added velocity and the Giants thought he should switch to a four-seamer. The truth, though, was that he never quite felt comfortable trying to be an up-in-the-zone, four-seam pitcher. Perhaps this would feel more natural.

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But then COVID hit, shutting camps down. While play eventually resumed in the summer, Webb’s performance was uneven in a shortened Year 1 of his new self. He struggled to command the ball, but there was a silver lining: all his pitches – his two-seamer, slider, and changeup – picked up movement, and the gains couldn’t be explained by spin-based movement.

Webb and Giants were tapping into something new.


Spin governs much of pitch movement. A force known as Magnus Effect makes a curveball curve and a fastball appear to rise. In 1852, German physicist Gustav Magnus was perplexed why cannonballs fired out of smooth-bore barrels often curved in unpredictable ways. He discovered that a sphere spinning through air will drag air around with it, creating a pressure differential. The shell moves toward the area of lower pressure.

Rifled barrels fixed the accuracy issues by creating a different type of spin: gyroscopic. It’s the same kind of spin that’s produced when a football is thrown in a spiral. Such spin is immune from Magnus Effect. (Most pitches thrown have an element of each type of spin, as the axis that the ball spins around is generally not perfectly in line to be 100% governed by Magnus or gyro spin.)

Those types of spins and their influence on projectiles have been known since the 19th century. More recently, a couple of college professors began considering another type of force governing movement not tied to spin, and their discoveries came just in time for Webb.

In 2012, University of Sydney physics professor Rod Cross published a paper and recorded a YouTube video demonstrating another way to make a ball move, separate from Magnus Effect: by creating pressure differentials via how seams were orientated on the ball, resulting in smooth and rough areas on the ball.

He included a pitch from a 2011 game as evidence, in which Freddy Garcia threw a split-fingered fastball that moved the opposite way that Magnus force suggested it should.