FORT MYERS, Fla. -- Twins left-handed reliever Ryan O'Rourke was diagnosed with a strained left flexor pronator mass in his forearm near his elbow, and he will open the season on the 10-day disabled list, general manager Thad Levine said Tuesday.
O'Rourke reported discomfort after his outing on Thursday against the Cardinals, and he underwent an MRI exam that revealed the strain. But there is no ligament damage, and O'Rourke is expected to take seven to 10 days off before starting a throwing program. The DL move can be backdated to March 30, which would allow him to be activated on April 9.
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"All things being considered, we viewed that as a good report from the MRI," Levine said. "But such as it is, it'll take him out of competition to make the 25-man roster. The good news was that the injury was related to the muscle and not the ligament."
O'Rourke was competing for a spot in the bullpen, allowing four runs in 6 1/3 innings this spring. He had a 3.96 ERA with 24 strikeouts in 25 innings with Minnesota last year.
He becomes the second Twins lefty reliever expected to open the year on the disabled list, as closer Glen Perkins hasn't progressed past throwing 20-pitch bullpen sessions every four days.
Levine said the organization plans to have a conversation with pitching coach Neil Allen and the medical staff about Perkins this week. He also wouldn't rule out Perkins being placed on the 60-day disabled list, which would open a 40-man spot.
"It wouldn't be our first choice," Levine said. "But we're also going to be attentive to how he'd be pitching in September than how he's pitching in April or May. So we'll be reliant on what Neil Allen and the medical staff feel is best for him to put him in position to be strong as possible for the second half."