Pittsburgh Pirates Prospects: 5 Breakout Seasons From 2021
By Noah Wright
No. 3 – infielder Diego Castillo
Diego Castillo isn’t going to be the last prospect that came from the New York Yankees and was in the midst of a breakout season in 2021. The Bucs acquired the infielder, along with Hoy Park, in exchange for struggling reliever Clay Holmes.
Castillo looked like he was turning a corner with the Yankee Double-A affiliate. His first 249 plate appearances of the season saw him post a .277/.345/.504 batting line, .367 wOBA, and 129 wRC+. Plus he blasted 11 home runs. Then once he was traded to the Pirates, he continued to hit well with Altoona. He only stepped to the plate 121 times but batted .282/.342/.445 with a 114 wRC+. Eventually, the Pittsburgh Pirates gave Castillo his first taste of action at Triple-A where he boasted a fantastic 146 wRC+, albeit in only 70 trips to the plate.
Many probably didn’t expect to see Castillo breakout for as much power as he did. He blasted a total of 19 home runs while having 24 doubles, and a .209 isolated slugging percentage. For comparison, Castillo doubled his 2015-2019 home run total in 348 fewer games. He didn’t even have an isolated slugging percentage of .100. The big reason he saw such a dramatic rise in power was a dramatic rise in fly balls, having a fly all rate above 40% compared to below 30% in 2015-2019.
Though he started to become power-happy, that didn’t affect his strikeout or walk rate. Heck, it actually improved his walk rate. His 12.7% strikeout rate may be a single-season career-high but isn’t that far off from what he was doing previously. In any context, a sub-15% strikeout rate is fantastic. It’s even better once you consider he had a healthy 10% walk rate. A guy who avoids strikeouts like the plague draws some walks and does it all with a solid BA and a little pop is a combination you like to see.
Castillo can field second base, third base, and shortstop, so he’s quite versatile in the infield. The Pirates will surely protect him from the Rule 5 Draft. You don’t just let a guy who went from unranked to a borderline 45-FV prospect in a year go unprotected in the draft. He should be considered the next man up if Michael Chavis struggles at second base to start the season. With 2022 being his age-24 campaign, you have to imagine he gets an extended look in the majors sometime next season.