Curvelo will return to the big-league club for the first time since June 13. With Round Rock, the 25-year-old has posted a 6.75 ERA, 1.68 WHIP and 24:16 K:BB through 22.2 innings this season. Texas optioned Winston Santos to Triple-A to free up space for Curvelo on the active roster.

Texas added Curvelo to its bullpen Thursday, but he'll head right back to Triple-A after giving up three earned runs in one inning Friday against Boston. The 25-year-old now owns a 7.56 ERA and 1.92 WHIP through 8.1 innings with the Rangers this year and will likely have to show signs of improvement at Round Rock before getting another shot in the big leagues. Joe Ross was selected to the active roster in a corresponding move.