As an outfielder for four years at St. Mary’s College, three of which were as a starter, Tony Gonsolin hit .305/.383/.453. During the summer after his junior year, he was an all-star for the Madison Mallards in the prestigious summer collegiate Northwoods League, slugging 11 home runs and hitting .316/.403/.510 with a wood bat. Moonlighting as a pitcher, Gonsolin never struck out more than a batter per inning at St. Mary’s and had nearly as many games saved as he did games started. He was drafted as a senior in the ninth round of the 2016 draft as a pitcher – a decision that was a surprise to some, given his power potential in the outfield and lack of refinement on the mound. In Gonsolin, the Dodgers saw a plus athlete with untapped skills who had immense upside if he focused solely on pitching.
On Wednesday, three years after being selected as a proverbial money saver, the first place Dodgers will call on Gonsolin to make his major league debut against the Diamondbacks. Gonsolin debuting as a big league starter might be even more unexpected than him debuting at all. His first 61 professional appearances were all as a reliever, and it wasn’t until he opened the 2018 season as a member of the Rancho Cucamonga Quakes rotation that the transition from outfielder to reliever to major league starter began materializing.
Gonsolin’s professional career began in the hitter-friendly Pioneer League, as a member of the Ogden Raptors in 2016. There, as a reliever, Gonsolin touched 94 with his fastball and worked 89-92, flashing some feel for two different breaking balls. He displayed solid feel for his arsenal but lacked an out pitch. Still, the foundation was there. The delivery was clean and efficient and relatively low effort. The high arm slot with which he released the ball was repeated pitch-after-pitch. The athleticism was evident and the aptitude for adjusting on the mound was growing by the day.
Gonsolin came into the 2017 season with several refined aspects of his arsenal. During 2016 instructional league, he began focusing on a four seam-dominant approach, working hand-in-hand with several members of the Dodgers player development department to identify positive pitch characteristics using Rapsodo, Trackman, and high-speed cameras. Coming into spring training in 2017, he was part of a group of players who partook in an individualized weighted ball training program the Dodgers were running. His velocity, as a result, began to creep up throughout the season. During the spring as a member of the Rancho Cucamonga bullpen, Gonsolin’s velocity was in the mid-90s and he featured increased depth on his curveball.
Perhaps more importantly, his newfound split-change was a pitch with which he began to grow more and more comfortable, and hitters reacted aptly by routinely swinging through it. The expected wOBA against the pitch during the 2017 season was just .177, with a miss rate of nearly 50% and a chase rate above 60%. The addition of a swing-and-miss caliber split-change helped transform Gonsolin from someone who relied on breaking balls to miss bats into someone who was especially more effective against left-handed hitters with the dynamic change of pace. All the while, the aforementioned velocity increase continued coming on throughout the 2017 season. Eyebrows were raised during an outing in the California League playoffs, when Gonsolin took the mound against the Lancaster Jethawks and threw 13 fastballs, the slowest being 97 mph. He touched 100 three times.
Basically an entirely different pitcher, Gonsolin entered 2018 spring training as a soon-to-be 24-year-old armed with an upper 90s fastball, a swing-and-miss caliber split-change, and two breaking balls; he received honorable mention on that spring’s Dodgers list, but wasn’t ranked. When then-new farm director Brandon Gomes and pitching coordinator Don Alexander approached him about the possibility of transitioning back to starting – a role he hadn’t taken on since he started five games as a college senior – Gonsolin proved to be up to the challenge. Maintaining mid-90s velocity with rise as a starter, his slew of offspeed pitches continued to refine. In 128 innings between High-A and Double-A, he struck out 155 batters and walked 42 and was named Dodgers Minor League Pitcher of the Year.
Entering the 2019 season, Gonsolin ranked sixth on FanGraphs’ Dodgers prospect list; Eric Longenhagen and Kiley McDaniel highlighted him as a 2019 Pick to Click during Prospects Week. An early season oblique injury slowed, but his stuff has largely returned to form in his 26 Triple-A innings. Perhaps most impressive has been his ability to keep the ball in the ballpark despite being a fly ball-heavy pitcher. Likely due to surrendering weak contact, Gonsolin allowed just eight home runs across those 128 2018 innings and just one in the extremely hitter-friendly confines of the 2019 Pacific Coast League.
His quiet, matter-of-fact approach to his craft has been part of his success thus far and will likely be evident to onlookers. His abilities on the mound likely will be as well. Gonsolin went from a mid-major Division I outfielder to a decent minor league reliever to a prospect who is capable of throwing 100 mph and will show three separate above average offspeed pitches at any point in time. On Wednesday, he’ll take another step in his unique career path – the biggest of all to this point – and take the mound as a major league starter.
Josh Herzenberg has served as an area scout and a minor league coach for the Dodgers. He can be found on Twitter @JoshHerzenberg.