Diego Castillo (born January 18, 1994) is a Major League Baseball pitcher for the Seattle Mariners of the Dominican Republic (MLB). He formerly played for the Tampa Bay Rays in Major League Baseball.
Castillo signed with the Tampa Bay Rays as an international free agent in March 2014. He made his professional debut that season with the Dominican Summer League Rays and spent the whole season there, going 3–3 with a 3.96 ERA in 25 innings.
In 2015, he played for both the Hudson Valley Renegades and Bowling Green Hot Rods, compiling a combined 1–2 record and 3.03 ERA in 18 relief appearances.
In 2016, he pitched with both Bowling Green and the Charlotte Stone Crabs, posting a combined 3–6 record and 2.98 ERA in 60.1 total innings pitched out of the bullpen.
Castillo was promoted to the Tampa Bay Rays and made his debut on June 6, 2018. For the season, he split time between the bullpen and being one of the Rays’ “opening” starters. Castillo threw 56+2⁄3 innings over 43 games, going 4–2 over 11 starts. He finished the year with a 3.18 ERA, 65 strikeouts, and 18 walks.
In 2019, Castillo was used as both a closer and opener. On June 23, he was put on the 10-day injured list with shoulder inflation. He finished the season appearing in 65 games (6 starts).
Diego Castillo has one child, unfortunately, there is no information about his child, except for the fact that Diego became a dad in July 2020.