Red Sox claim right-handed reliever Max Castillo off waivers

BOSTON -- Craig Breslow added some more depth to the Red Sox bullpen on Tuesday, claiming right-handed reliever Max Castillo off waivers from the Kansas City Royals.

Boston will be the third team for Castillo in as many years. The 24-year-old Venezuela native initially signed with the Blue Jays as an international free agent in 2015, and broke into the big leagues with Toronto in 2022 when he made six starts and appeared in 14 games overall.

He was traded to Kansas City in August of 2022 as part of the package that landed infielder Whit Merrifield in Toronto. Castillo allowed 19 runs over 18.2 innings after being acquired by the Royals, giving up 23 hits and issuing 10 walks over his five appearances.

Castillo spent most of his 2023 season with Triple-A Omaha, making 21 starts for the Storm Chasers and compiling a 6-7 record with a 4.58 ERA and 1.250 WHIP over 116 innings. He also made seven appearances out of the bullpen for the Royals last season, allowing 10 earned runs over his 20.1 innings of work.

In 21 career Major League games, Castillo owns a 5.43 ERA and 1.374 WHIP over 59.2 innings. He has pitched well in the Venezuelan Professional Baseball League this winter, going 5-0 with a 2.72 ERA over nine starts (and 11 games total) for Cardenales de Lara. 

Castillo is taking up the final spot on Boston's 40-man roster, so Breslow will have to make another move before the Red Sox officially add starter Lucas Giolito. Boston and Giolito reportedly agreed to a two-year deal last week, though no announcement has been made by the team.