How Are Each of These Pitchers Throwing Harder This Year?

Each season, there is a group of pitchers across the league who have notable velocity increases. In the age of hard throwers, it’s important to make sure you’re keeping up with the rest of the league. Every pitcher has a different situation, too. Some will adapt their body to increase how fast they move, and others will make a slight mechanical adjustment to clean up their kinetic chain — or a pitcher can do a combination of both those things.

For this piece, the focus will be on slight mechanical adjustments that three specific pitchers have made this year that have allowed them to gain velocity. The interesting thing about this group is the difference in size variation and mechanical traits. There isn’t one single way to throw hard, and this group is a great way to highlight that.

Kenley Jansen, Avg. Velo Increase: 92.6 mph to 94.5 mph

2022

2023

There was no expectation for Kenley Jansen at age 35 to recover the velocity he had in 2016, but he had other plans. Per Baseball Savant, his 94.5 mph average fastball velocity is the highest of his career. What’s more, after using the highest release point of his career last season, he has dropped back down to his career norms (6.27 ft), pairing it with a career low in average horizontal release point (-2.25 ft). Between 2017 and ’22, he had progressed more and more toward the center of home plate (-1.96 ft to -1.16 ft).

This change has allowed Jansen to align better the direction of his torso rotation. Last year, he put himself in a position of extreme spinal flexion and lateral torso bend in order to get his release point as high as possible and centered over home plate. That sent most of his momentum into more of a spinning action down the mound rather than driving down and using the strength of his lead leg block (foot plant) to control his force. In 2022, when his stride foot first struck the ground, his torso was already beginning to lean toward first base. That has changed this season: his torso is better stacked over his pelvis as he drives and rotates down the mound. It’s night and day.

Keep that idea of improved torso stacking in mind as we look at the changes the next pitcher has made.

Freddy Peralta, Avg. Velo Increase: 92.6 mph to 94.4 mph

2022

2023

Like Jansen, Freddy Peralta is throwing harder than he ever has in his career. One of the main reasons I enjoy watching him pitch is because of his abbreviated windup; it’s not a strategy that you see many pitchers employ. He slightly adjusted his windup this season compared to last, which has been a key contributor in the velo jump.

Before diving into that, let’s take a look at his change in release point. There’s been none vertically speaking, but there has been a shift horizontally more toward third base (-2.59 ft to -2.8 ft). At first, I thought him shifting positions on the mound was causing it, but as you can see, he is still all the way to the left side of the rubber.

Peralta’s windup was always quite fast, but in watching his video from last season, it did feel a bit rushed. Pitchers who use the old fashioned “hands over the head” style during the windup don’t typically do it so quickly. It’s a movement that allows an athlete to feel the connection between their upper and lower body; the point of it is to take your time in establishing rhythm rather than rushing through it.

This year, the windup is remarkably slower, letting Peralta properly stack his center of gravity over his pelvis as he prepares his forward movement down the mound. Last year, the quick movement of his hands over and back to his chest forced his momentum in a suboptimal direction, and he didn’t get into his full hip hinge until he was already moving down the mound, making him spin his center of mass around instead of holding the counter rotation down the mound as long as possible. He just looks whippier this season, and it’s the reason he has been able to get up to 97–98 mph at an impressive rate.

Reid Detmers, Avg. Velo Increase: 93.2 mph to 94.9 mph

2022

2023

Reid Detmers’ season has been weird. His strikeout rate is up, and he is allowing fewer home runs, resulting in a 3.41 FIP — and a 4.79 ERA. I think there is reason to believe this will even out as the season progresses, because to me, this is best version of Detmers we’ve seen.

From a release point perspective, he is in a similar spot as Peralta: vertically, nearly nothing has changed, but horizontally, he has shifted much closer to the right-handed batter’s box. He has moved toward the right side of the rubber, but there is still a key mechanical difference happening here.

Of all the pitchers discussed in this piece, Detmers’ change is the most disguised. With Jansen, the mechanics were obviously different. With Peralta, a change in pace allowed him to better align his body. But with Detmers, the windup and use of his glove side are nearly identical. To me, the key difference comes from his position at peak leg lift: he shifted his hands closer to his hip pocket and to the letters on his jersey. That changed his center of mass as he prepared to move down the mound.

There are a few things at play here, but the main one I want to focus on is the stripe on Detmers’ pants. In 2022, it looks like his leg folded over into his knee as he moved down the mound. This season, there isn’t any folding over or collapsing; he holds his position in his hinge, then quickly fires his back side without driving his knee into the ground. When pitchers say things like “I’m using my legs more,” this is what they’re talking about.

Pitching mechanics will always fascinate me. Pitchers adapting their mechanics to get more out of their bodies is the reason why we’ve seen this trend of increased fastball velocity over time. Pushing yourself to change is difficult, so when pitchers like Detmers, Peralta, and Jansen all do it in different ways, it’s necessary to discuss in detail.