Thielbar missed the Twins' past 29 games, last pitching May 2 in a loss to the Chicago White Sox, due to a right oblique strain. In 11 appearances this season, the 36-year-old Thielbar is 1-0 with a 1.80 ERA, two walks and 10 strikeouts in 10 innings.
In a corresponding move, the Twins put right-hander Cole Sands on the 15-day injured list, retroactive to Thursday, with a right shoulder impingement.
Sands, 25, who last pitched on May 30, has a 0.73 ERA over 12 1/3 innings. He has walked seven and struck out 13, with opponents batting .213 against him.