Needing to clear room on their 40-man roster for some procedural moves , the Red Sox designated relief pitcher Luis Guerrero for assignment Thursday.

Guerrero, 25, appeared in 13 games for the Red Sox this past season, compiling a 4.15 ERA. The previous year, when he made his major league debut, he made nine appearances and didn’t allow a single run.

He flashed an electric fastball that sometimes registered in the upper 90s, but he frequently had trouble with his control. In 17.1 innings with the parent club in 2025, he issued 14 walks.

Guerrero was born in the Dominican Republic, but spent much of his time growing up in the Boston area, attending high school there after his family moved to Jamaica Plain. He was a 17th-round draft pick in 2021 and spent the next two years in Boston’s

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