Maximo Alberto Castillo (born May 4, 1999) is a Venezuelan professional baseball pitcher for El Águila de Veracruz of the Mexican League.

He has previously played in Major League Baseball (MLB) for the Toronto Blue Jays and Kansas City Royals.

[4] Castillo was in the majors for a couple days before being optioned back down to Buffalo, but he was recalled on July 7, after Blue Jays starting pitchers Yusei Kikuchi and Kevin Gausman came down with injuries.

On August 2, 2022, the Blue Jays traded Castillo and Samad Taylor to the Kansas City Royals in exchange for Whit Merrifield.

[9] He appeared in 5 total games (4 starts) for Kansas City down the stretch, struggling to an 0-2 record and 9.16 ERA with 17 strikeouts in 18+2⁄3 innings pitched.

[16] In 14 games (13 starts) split between Lehigh and the Double–A Reading Fightin Phils, he struggled to a combined 0–6 record and 7.62 ERA with 40 strikeouts over 52 innings of work.