Del Castillo, Arizona's catcher, is the top FAAB target in Week 21 with around 5% ownership. In shallow catcher pools, a smart bid could yield a valuable contributor in both power and on-base categories. His spot in the Diamondbacks’ lineup suggests multi-category upside if he receives regular at-bats and stays healthy.

Del Castillo’s three-run homer put Arizona ahead early, marking his first long-ball of the season and signaling breakout potential amid Arizona’s early-season surge. His power at the top of a productive lineup creates immediate fantasy upside, particularly in 12-team leagues and daily formats that reward early-game production.

Adrian Del Castillo has shown promise in limited MLB action and could capitalize on increased at-bats if the Diamondbacks make roster changes.

Adrian Del Castillo caught Corbin Burnes for the first time this spring, which is critical for establishing rapport. Burnes is focused on developing relationships with his catchers, highlighting the importance of teamwork in pitching success.

Adrian Del Castillo is a 25-year-old homegrown prospect for the Diamondbacks, who could potentially surpass both José Herrera and René Pinto in the catching hierarchy as Spring Training approaches. His development and performance during this critical period will be closely watched, as he aims to establish himself as a viable option behind the plate.