6 SF Giants prospects who could make an impact this season: 1. Kervin Castro
Right-handed pitcher Kervin Castro was ranked the 26th-best prospect in the system heading into the season after a breakout performance in last fall’s instructional league and was added to the Giants 40-man roster and invited to big-league spring training. While he was overshadowed by fellow young fireballers Gregory Santos and Camilo Doval early in the year, Castro has quietly emerged as the best of the trio at Triple-A.
Castro relies primarily on a mid-90s fastball and power curveball that play off each other well. Developed as a starting pitcher until this season, Castro had never pitched in full-season affiliate ball until 2021. Faced with the massive challenge of a transition to the bullpen alongside a jump from short-season ball to Triple-A at 22, the young righty has responded admirably.
In the incredibly hitter-friendly Triple-A West league, Castro has made 26 appearances this season, racking up 52 strikeouts and recording a strong 3.23 ERA in 39 innings while surrendering 29 hits, 19 walks, and just three home runs. Since allowing two runs in his first appearance of June, Castro has been even better, recording a 1.86 ERA over his last 29 innings.
Just as importantly for the Giants, Castro has done something few other options for the front office have this season: consistently made multi-inning appearances. To lessen the transition to relief, the Giants have kept Castro on a relatively regimented usage pattern, often giving him at least two or three days between outings while pushing him up to (or beyond) 30 pitches. In fact, Castro has completed at least two innings in 10 of his last 16 appearances.
The Giants bullpen has been heavily taxed recently. Adding an arm comfortable being stretched to 50 pitches (51 is his season-high) and capable of pitching in high-leverage could be exactly what manager Gabe Kapler needs. With Kervin Castro already on the 40-man roster, it seems easy to envision him joining Doval and Santos by making his MLB debut in 2021.