The Rangers designated Curvelo for assignment Friday.
Curvelo was sent down to Triple-A at the start of the month and will now lose his 40-man spot as well to make room for Marco Gonzales, who was selected to the active roster Friday. Curvelo has given up 11 runs in 10.1 innings with the Rangers this year while also accumulating an 8.42 ERA and 1.83 WHIP over 25.2 frames at Round Rock.