Crain was 2-3 with an 8.15 ERA and 12 walks in 17 2/3 innings this season. He gave up the game-winning single to Chicago's Ryan Theriot in the ninth inning on Sunday that prevented the Twins from sweeping the Cubs.
Crain has been with the Twins since Aug. 1, 2004, posting a 3.57 ERA in 272 games. He had season-ending surgery to repair a torn labrum and rotator cuff in his right shoulder on May 29, 2007, but was 5-4 with a 3.59 ERA in 66 appearances last season.
"He took it about like anyone would expect," manager Ron Gardenhire said. "A little numb at first I'm sure. He wanted to know exactly what the plan was here, and the plan is for him to go down and get innings."
Perkins was placed on the disabled list with inflammation in his left elbow on May 19. He is 1-3 with a 5.36 ERA in eight starts this season and was scheduled to open Minnesota's series against Pittsburgh on Tuesday night.
Cuddyer missed the last two games with a strained right index finger, and Crede, who has a history of back problems, missed Sunday's game with a sore back.
"We play it game-by-game," Gardenhire said. "I check with him every day."
Outfielder Denard Span, out since June 9 because of a right inner ear problem that has caused dizziness, was diagnosed Tuesday with a virus that attacks a nerve that sends signals, such as balance, from the ear to the brain.
Medication has been prescribed, and Span is listed as day to day. Gardenhire said Span could go on the disabled list if he isn't ready to play in the next two or three days.