After spending seven years in the Boston Red Sox farm system (2013-2020), Jhonathan Diaz signed a minor league contract with the Angels on November 17, 2020. Prior to joining the Angels roster in September, the Valencia, Venezuela native began 2021 with Double-A Rocket City pitching in 13 games (nine starts). The southpaw went 5-3 with a 3.98 ERA and 78 Strikeouts through 61 innings.
On May 13, Diaz pitched against the Tennessee Smokies (Chicago Cubs affiliate), picking up the win after tossing 5.2 shutout innings, while yielding just one hit. The most impressive thing from his line score that night was the 11 batters he retired via the strikeout.