BY J.A. SCHWARTZ
By any reasonable measure, Jason Castro has been a success, earning a degree in Economic Sociology from Stanford, an elite academic institution. And in 2012 he married his college girlfriend Maris, a lacrosse player for the Cardinal.
Drafted by Houston as the tenth overall pick in the first round of the 2008 MLB Draft, Castro signed with the Astros for a $2 million bonus and was recognized as an All-Star in 2013.

Castro and his wife have been active in their community, and they helped found “Castro’s Kids”, a literacy program that provides books for Houston area schools, where he made his Major League debut with the Astros. In May 2016, they celebrated the birth of their first child.
But despite all his achievements, Jason Castro has yet to achieve the goal that countless millions of kids strive for from the day they first pick up a bat, to win a championship. Playing for the Minnesota Twins this season, he may be closer to realizing that dream than he’s ever been in his career, and he’s dramatically changed the way he plays the game to help drive his quest.
It’s the second time in his career that he’s made significant alterations to his playing style, and in each instance the results have been definitively positive. However, as the Twins arrive in Oakland for a three-game series starting Tuesday, that World Series ring has continued to elude him.
After a storied career at Castro Valley High School in California, Castro was selected in the 43rd round of the June 2005 MLB draft by the Boston Red Sox. Castro elected not to sign with Boston, and instead chose to matriculate at Stanford in the fall of 2005. The Red Sox would go on to win World Series Championships in both 2007 and 2013.
Castro helped lead the Cardinal to the 2008 College World Series, where his team was eliminated by the eventual champion Georgia Bulldogs in the semifinals. He was named Stanford’s MVP that year, and was included on the Series All-Tournament team.

Named the 53rd best prospect in baseball prior to the 2009 season by Baseball America, Castro ascended to the 41st overall prospect in the rankings released before the 2010 season. On June 22, 2010, he made his major league debut, and singled off Tim Lincecum, the two-time defending Cy Young Award winner. He would go on to hit .205/.286/.287 for the Astros that summer. By making his debut, and staying in the majors long enough to earn a chance to play regularly, Castro beat the odds. According to Baseball America, only 17.6% of players drafted ever make the major leagues, and only 9.8% stick around long enough to generate any true value to their teams.
Coming into the 2011 season with a chance to be included on the Astros 25 man roster, Castro had an opportunity to break camp with the team as its starting catcher. However on March 2nd, he landed awkwardly on first base running out a routine ground ball, tearing his right ACL. He would have surgery two days later, and miss the entire season.
After brief stops in the minor leagues to begin the 2012 season, Castro became the Astros primary catcher, and hit .257/.334/.401. He had cemented his position as a full time player in the major leagues, though the Astros had very little success as a team, finishing 55-107, the worst record in baseball.
Castro’s 2013 season was his best to date, hitting .276/.350/.485 and was named an All-Star that year. While his work at the plate was laudable, his work behind it wasn’t helping his team nearly as much as the Astros new leadership would have liked, and the organization asked him to make changes in how he caught pitched balls, the lifeblood of a catcher.
Under the direction of Jeff Luhnow, the new Houston GM, the organization prioritized the art of pitch framing. Pitch framing is the process of receiving the baseball as a catcher in a way that maximizes the likelihood of that pitch being called a strike by the umpire. Baseball Prospectus data had shown that the best practitioners of this skill could end up saving their teams as many as 30 runs per year compared to the average catcher. That kind of competitive edge appealed to the Astros. In 2012, Castro ranked 104th in this metric, costing his team 19 runs by the way he received pitches, according to Baseball Prospectus. As the Luhnow administration took over, they began to implement many of their new strategies, and pitch framing was something they wanted to improve across the organization. Castro became an early test case.

In 2013, Castro improved to 79th overall in baseball by the BP metric, rating a net two runs below average for the Astros. That would be the last season he would receive a negative rating with regards to his framing skills. Over the next three seasons, he ranked 10th, 13th and 3rd best in all of baseball as a pitch framer, peaking with the 2016 season with 17.7 runs saved above the average catcher.
Largely on the strength of his pitch framing prowess, Castro landed a three year contract with Minnesota on November 30, 2016 worth $24.5 million. Twins catchers had been among the worst pitch framers in 2016, with Kurt Suzuki and Juan Centeno ranking 94th and 101st by BPs metric, costing the Twins pitchers more than 18 runs compared to the average backstop. Castro’s skill in this area certainly appealed to the Twins leadership, and he left for Minnesota for the 2017 season.
His acumen behind the plate helped improve Minnesota’s catching dramatically in 2017, leading to a personal 7.7 runs above average framing score that represented a nearly 25 run net gain over their previous catching efforts by that metric. Not coincidentally, the Twins made the playoffs in 2017 with an 85-77 record, a 26 win improvement over the previous season.
Castro’s contributions had been instrumental in their improvement, and despite a .242/.333/.388 batting line, his receiving helped the Twins improve their ERA from 5.08 in 2016 (29th out of the 30 teams) to 4.59 in 2017. Castro’s Twins lost the Wild Card game to the Yankees that postseason, and he watched from his couch as his old friends and former teammates in Houston won the AL pennant and the World Series title without him.
In the past, Castro had worked with independent hitting consultant Craig Wallenbrock, a former scout for the White Sox, A’s and Indians. Though Castro hasn’t indicated publicly exactly how he’s changed his approach at the plate in 2019, it is reasonable to consider that his continued work with Wallenbrock has contributed towards the current iteration of his batting style.
On June 18th, Castro turned 32, and this season he’s made significant changes to his offensive approach. According to Statcast publicly available data, Castro has become one of the most dangerous hitters in baseball this year, a marked departure from his offensive profile for the past five years.

Average exit velocity, which measures the speed at which the ball leaves the bat is a primary Statcast metric. In 2019, Castro has a 92.2 MPH exit velocity, the highest of his career, and well above the MLB average of 88.3. That figure ranks him 21st in the majors, and ahead of both JD Martinez (92.1) and Mike Trout (91.9) this year. Among catchers, only Gary Sanchez of the Yankees has better exit velocity numbers in 2019.
How did Castro change his approach at the plate to achieve the impressive results he has thus far in 2019 ? Hitting is an incredibly complex process, where a batter must make decisions in fractions of seconds as pitches come at them with spin and movement at up to 100 MPH. It is unreasonable to imagine that a single adjustment made Castro into the 2019 version, but there is an explanation that has some correlation to the results: he changed his swing plane, opting for a greater uppercut at the plate.
Ted Williams, in his seminal tome “The Science of Hitting” (published in 1971), espoused a swing that had a slight uppercut. Williams’ theory was to tailor his swing to achieve a bat path that more closely mirrors the plane of the incoming pitch. The vast majority of pitches move in a slightly downward trajectory after being released by the pitcher from up to ten feet off the ground towards a strike zone two to four feet off the ground. His thinking on the subject ran counter to some of the methods batting coaches had taught for decades, but that very practice has now become commonplace for the modern hitter. Castro is just one of the latest disciples of this line of thinking.
Castro is hitting the ball in the air in 2019 at a far greater rate than at any time in his career. The primary indicator of Castro’s concerted effort to lift the ball more regularly comes from the launch angle of his swings. The launch angle measures the angle at which the ball comes off the bat, with higher numbers correlating with more lift at impact, and more fly balls as a result. Castro’s launch angle in 2019 is 16.9, well above the 13.0 angle he featured through 2018.
The combination of changes Castro made to his swing entering the 2019 campaign has led to significant improvements in his offensive profile. Castro is hitting more fly balls than ever before, and when he does make contact, the ball is leaving his bat with higher velocity and is flying further than at any point in his career to date. His .231/.323/.487 performance this season represents a career high in slugging percentage, the best measure of the damage he’s doing when impacting the baseball.
The numbers only support what the eye can see. Jason Castro is both an offensive and defensive asset, helping lead the Twins first half surge to the top of the AL Central. Considering the likelihood that Minnesota makes the playoffs, the changes he’s made to his game over the course of his career, both offensively and defensively, may finally help guide him and his team to heights he’s previously never reached.
Great article! Good to see Castro turn his career around with a breakout team