In December 2022, the Twins signed utility player Willi Castro to a minor league deal with a spring training invite. The former Detroit Tigers’ prospect impressed at Fort Myers, hitting .250/.375/.575 with ten hits, three home runs, two doubles, and swiping three bases in 40 at-bats. Castro’s performance earned him a spot on the team’s 2023 Opening Day 26-man roster.
The then-25-year-old initially had a limited role. Castro started once or twice a week, and Minnesota used him as a late-game pinch-runner. Still, his surprisingly impressive early-season offensive performance and extensive defensive versatility earned him an integral role on the contending Twins. Castro stayed on Minnesota’s 26-man roster, hitting .257/.339/.411 with 92 hits, nine home runs, 18 doubles, 33 stolen bases, and an impressive 109 wRC+ over 409 plate appearances in 124 total games. Castro displayed his complete versatility, playing 576.2 innings in the outfield and 286.1 innings in the infield.
Spring training is in full bloom, Opening Day is a little over a month away, and Castro looks like he’ll be Minnesota’s primary utility player. Based on his stately performance last season, the Río Piedras, Puerto Rico native, deserves a more significant role with the playoff-hopeful Twins this season.
However, with real expectations and the anomaly of surprise no longer on his side, the fan-favorite’s goodwill could quickly burn out. Castro performed exceptionally well toward the end of last season. He generated a 134 wRC+ from August 1 through September 1, which warrants optimism heading into next season. Still, MLB pitchers and coaching staff will always make the necessary adjustments to get the upper hand over opposing hitters. What adjustments must Castro make to ensure he continues to excel in his second season in Minnesota?
Castro’s swing-and-miss rate on fastballs has been his Achilles heel throughout his career, especially last season. Last season, Castro saw 1,002 fastballs and swung and missed often (26 percent whiff rate). Castro tends to be aggressive against fastballs. A switch-hitter, Castro saw 506 breaking balls and 332 offspeed pitches last season but whiffed at only a combined league-average 34 percent of them.
As a team, the 2023 Twins led the league with a 26.6 percent strikeout rate while generating the most strikeouts in single-season history with 1,654. In this context, Castro’s 24.3 percent strikeout rate is respectable. Still, a player struggling with velocity in today’s game is reason for concern. It is one of a modern hitter’s most easily exploitable deficiencies. It will be interesting to monitor how often Castro sees higher velocity pitches and his ability to adapt to them.
Castro also struggles with pitches low in the zone, evidenced by an 85% whiffs per swing rate on pitches low in and below the strike zone. Of the 695 pitches Castro saw in 2023, 238 were below or low in the strike zone. In 2023, most pitches Castro faced were middle-low (8.21%), and pitchers will inevitably approach Castro the same in 2024 to maximize their ability to generate whiffs.
Castro’s numbers with the Tigers suggested he was better from the right side of the plate. However, his performance with the Twins last season bucks that trend.
Below are Castro’s 2023 splits:
- As a right-handed hitter: .237/.320/.316, 129 plate appearances, 27 hits, one home run, six doubles, 11 walks, 26 strikeouts
- As a left-handed hitter: .266/.348/.455, 280 plate appearances, 65 hits, eight home runs, 12 doubles, 23 walks, 73 strikeouts
Castro performed better against right-handed pitchers in a large sample size. Having hitters who hit right-handed pitchers well is beneficial because most opposing starting pitchers throw from that side. However, Castro’s skill set has become redundant for the Twins. Castro’s splits are inconsistent, meaning how well the 26-year-old will hit from each side of the box is a pertinent unknown. No switch-hitter will ever equally produce from both sides of the plate. Still, if Castro progresses as a right-handed hitter and continues to produce as a left-handed hitter, it would solidify him as Minnesota’s primary utility player.
Castro’s versatility and above-average defense – 79th percentile Outs Above Average at Baseball Savant (OAA) – provide significant value, particularly during a strenuous 162-game season. Still, his offensive shortcomings are concerning, especially for a team with lofty goals. Regardless, with Twins second-ranked prospect Brooks Lee and promising young utility player Austin Martin close to the big leagues, Castro’s spot on Minnesota’s 26-man roster could become expendable if he struggles next season.
