New Phillies hitting coach Peter Fatse made a pit stop before moving on to his next gig.
After being let go as Boston Red Sox lead hitting coach in late April, Fatse joined the Tampa Bay Rays as a hitting consultant, where he studied swing mechanics in the club’s analytics department.
Per Rob Brafford of WEEI, Fatse joined the Rays organization two months after his dismissal from Boston. He was put in touch with former Texas Rangers GM and now Rays senior advisor Jon Daniels. The Rays wanted a fresh perspective.
Specifically, Fatse worked with the hitting analysts responsible for overseeing the output from KinaTrax, a motion capture biomechanics tracking system used on both the hitting and pitching side around major league baseball. It’s a precise way of breaking down a player’s individual movement patterns and seeing if anything is in disarray in real time.
The Phillies, who are heavy investors in biomechanics, have been using KinaTrax since at least 2024. Investing in the new technology is step one. Finding the right people to translate the information to the players and make it useful is step two.
Fatse was familiar with the system from his time in Boston. He spent his short tenure with the AL-champion Rays learning more about it.
“It was more of a creative lens at times,” Fatse said in a Zoom meeting with local reporters on Friday afternoon. “How can we use this information to, you know, to get more granular, deeper within the swing and basically get a better understanding of the individual aspects within a swing that we can use for, again, modeling, coaching and development. So I spent a lot of time in that space.”
Fatse credited Rays assistant director of R&D Tim Morales with helping him gain a new perspective on how to get the most out of the information.
“Just the way he deconstructed the information, I just felt like the way he processes the information, it was eye-opening for me,” Fatse said. “Just how he deconstructed the swing. I thought it was really helpful for my understanding.”
The modern MLB hitting coach is many things. Sometimes, Fatse will need to be the voice of reason when his hitters are deep in their own minds as they slog through a long slump. Hitting coaches are also responsible for game planning, communicating the opposing pitcher’s arsenal before at-bats and going over swings on the iPad after at-bats. He’ll bring over Joe Cronin (not the long dead Hall of Famer) with him from Boston to assist with some of the duties. Edwar Gonzalez, who was hired last year as an assistant hitting coach, was retained.
But perhaps the most important task for Fatse and his staff in year one is to gain the trust of a hitting group led by veterans whose time with former hitting coach Kevin Long dates back to their days in Washington.
Fatse was first hired by Boston as an assistant hitting coach prior to the 2020 season. His experience with veterans, from J.D. Martinez to Xander Bogaerts and even Kyle Schwarber for a very short time in 2021, will help him navigate the challenges of establishing credibility in Philadelphia.
“It starts with just trying to get a better understanding of why they do what they do and what’s helped them get there,” Fatse said. “When I was named an assistant in the fall of ‘19, obviously J.D. Martinez was a super impactful player for us. A guy that I learned a ton from early on in my career. … We had a strong veteran presence in those early years. And for me, it was, obviously, you can see things from across the field to a degree, right? Like, you can study video. I can get into the advanced analytical information and paint a picture, but the reality is that the why is the most important part to me as a coach.
“You have to understand why somebody does something or what has helped them get to this point. My mentality is you have to understand and appreciate those things before you jump in and make an assumption, right? So I think hitting is always a collaboration with the player. With players with 10+ years in the big leagues, it’s even more of the case. They have more runway in their careers. I think it’s just understanding those things.”
And while his work with the Rays was mostly remote and specialized, the organization did have an impact on him.
“The thing that I would say that struck me was just the culture,” Fatse said. “Just the culture from top to bottom, it seemed like everyone was aligned and on the same page. Trying to find ways to get better in whatever department they were in.”
