The Twins added lefty Gabriel Moya to their roster after the 22-year-old helped Class AA Chattanooga to the Southern League playoff title.
To make room for Moya on the 40-man roster, infielder Engelb Vielma was designated for assignment or release.
Moya, acquired from the Diamondbacks for catcher John Ryan Murphy in late July, was a combined 6-1 with a 0.77 ERA and 87 strikeouts in 58.1 innings for Chattanooga and Class AA Jackson (Tenn.).
He will wear No. 58 tonight when the Twins play host to the Padres.