The Twins announced the move one day after Nolasco left the team in Seattle to return to Minnesota for an examination.
The Twins signed Nolasco to a $49 million, four-year deal in the offseason to bolster one of the league's worst starting rotations. But he is 5-7 with a 5.90 ERA in 18 starts this season.
Nolasco told the Twins on Monday he has been pitching through discomfort in his elbow all season.
"It's good there is no major thing here, nothing structurally too awful bad. Now it's about getting the soreness out, getting the stiffness out, time probably better than anything else and we'll see. We'll see where it goes from there," manager Ron Gardenhire said. "Let him take some time, do some treatment with the trainers and see how he responds to that. Obviously the throwing is not making it better."
The Twins recalled catcher/outfielder Chris Herrmann from Triple-A Rochester. Gardenhire did not announce how they would replace Nolasco in the rotation. He was scheduled to make his next start this weekend in Colorado against the Rockies.