A New Era in Bay Area Baseball: The 26 Draft – Diego Castellanos

Welcome to Part 2 of the blog series, A New Era in Bay Area Baseball: The 26 Draft. We will feature the 7 members of the #kpicrew that saw their names called in the 2026 MLB Draft.

Diego Castellanos – He Just Keeps Coming

If you have been around Diego (Diggy) during his progression of a baseball player, you know he can ball a little bit… but you never really notice him too much. He is quiet, does not draw attention to himself, and he blends in with the crowd during training and practice.

But what he does on the field during games is anything but quiet. He has been overshadowed for his entire baseball journey, but he just keeps doing what he always does… he just keeps hitting, he just keeps working… and he just keeps coming and we don’t plan on him stopping anytime soon.

Diggy’s Story

Diggy grew up in a sports family. His father is a coach and he grew up the oldest brother of 4 boys that were (and still are) into athletics. He grew up in Newark, but the family decided they wanted a more community orientated environment long term and moved to Morgan Hill right before Diego started high school.

As a smaller and underdeveloped player, Diego just blended into the local baseball scene when he arrived in Morgan Hill. Covid disrupted his freshman season at Live Oak High School, but it also provided him exactly what he needed… time to dedicate to physical development and building big tools that would help him down the road of his baseball journey. He completely immersed himself into KPI’s training and pursued both pitching and hitting at our facility. Being left handed and undersized, we weren’t sure of his progression as a hitter and we wanted to leverage his left arm to make sure he had a chance in the recruiting process.

After an intense Summer/Fall/Winter of training, Diego enjoyed a solid but unspectacular sophomore season and continued to prioritize his training. He was a skilled and smart ballplayer, but he lacked the physicality to compete for bigger prizes and the thought of his recruiting process beginning like some of his peers was not a reality. He played for a local travel team (not a national one) and he stayed on the grind with his physical development throughout his Junior year.

Going into his Junior season at Live Oak, it was still unclear if he was a hitter or a pitcher long term, but he decided to solve that problem himself by putting up a monster season and being named MVP of his high school league as a hitter. His long term direction was now clear, but he still didn’t have the physical set that would attract Division I recruiters. He continued to gain weight and size through the Summer before his senior season and he continued to produce in tournaments and some targeted college prospect camps.

KPI led his recruiting process and we knew we had to stay patient. We targeted high academic schools in this process because we knew his academic prowess would separate himself from others and we would also be able to secure some academic scholarship money to help his family see his dream become a reality. During this entire process Diggy only received one Division I scholarship offer, and he committed to Saint Mary’s College in the Fall of his senior season.

While at Saint Mary’s, Diggy had a similar progression as he did in high school. He did not play much his freshman season and he had to continue his commitment to enhancing his physical tools to keep up with higher level, older players. He of course, did the work, and became a more physical presence that could match up with the older players in the program and the high level of play that Division I provides. He went to play full time as a sophomore and then had a monster junior season, culminating in a 37 game hitting streak and an appearance in the NCAA Regional, where SMC beat the #1 team in the country, UCLA.

Diego was drafted by the New York Yankees at the conclusion of his junior season. This incredible accomplishment was the culmination of an improbable journey where he had to scratch and claw for everything he received, nothing was easy or handed to him. But he wouldn’t have it any other way, as that is who he is. He has had a successful start to his professional career and we look forward to watching him on TV someday!

Diego’s Journey at KPI

Diggy’s path at KPI wasn’t straight and easy, but we always knew we had a path because of his intense belief in our process and the work he was willing to put in. We have an athlete-centered environment at KPI to allow motivated players like Diego immerse themselves in our systems and push their limits based on their own, internal motivation.

Strength @ KPI: For most of Diego’s high school career, he was undersized and his strength focus was very straight forward… gain weight and increase force production. He did not interact well with the ground, meaning he was leaving a lot of force production on the table. Body weight is one of the main drivers of force production, so as he steadily gained weight, we saw his bat to ball skills start to lead to higher production on the field. We stayed with a steady, consistent approach to his lifting since his progress was always clear and his production matched his work. Sometimes the best strength programming is running the system that is working. Now that Diego has reached physical maturity and is much more forceful than the younger version of himself, our focus has shifted towards timing of movement and mobility.

HItting @ KPI: Much like his strength, Diggy’s hitting at KPI has been a fairly straight forward approach. Even before he got big and strong, Diego displayed advanced barrel to ball skills and his swing metrics and path fell within our desired ranges. The only metric that we needed to improve was bat speed. Our dual areas of focus’ for his entire time at KPI (7 years now) was to improve his bat speed and put him in stimulating and challenging environments. For bat speed, along with our strength programming, he used our Proteus and approach with weighted training bats to gradually improve his bat speed. Since bat speed has the strongest correlation to hitting success and he already had some barrel control, we knew we had to go all in on bat speed and that has paid massive dividends. From an environmental perspective, hitters like Diggy thrive in our environment. He doesn’t do useless tee work or work in comfort, he immerses himself in a challenging environment where if he performs and executes the tasks we give him, he will inevitably be better situated to perform on the field… and he most certainly has performed.

Diggy’s Next Steps

We are excited to welcome Diego home soon as he finishes his first professional season. We will re-assess him, work with the Yankees and his agent on his offseason programming, and we will see him in the facility on a daily basis as he advances his path to the major leagues.

He was never the star or the favorite to make it, but he just keeps coming… and our money is on him.