FORT MYERS, Fla. -- The Twins received a blow to their pitching staff on Saturday, as right-hander Trevor May was diagnosed with a torn ulnar collateral ligament, general manager Thad Levine announced.
May, who is competing for the fifth spot in the rotation, will get a second opinion on Sunday, but season-ending Tommy John surgery is a possibility. If May has the surgery, he's expected to be out about 12 months.
"Your first thoughts go to the player having to deal with something like that," Twins manager Paul Molitor said. "We know the work he put in this winter for his back, and then to have his elbow blow like that. It's a tough blow for our team."

May, 27, has a career 5.14 ERA with 214 strikeouts and 65 walks in 203 innings. He moved to relief during the 2015 season and remained there last year, but he was getting the chance to return to starting this season. He dealt with back issues each of the past few years, but he had worked to shorten his delivery to take stress off his back.
"It's a big blow, especially with how last year went and trying to get back to where it was," May said. "I was excited. Unfortunately, I'm not going to be able to do that this year."
He's been upbeat with the way this camp had been going and was likely the frontrunner for the fifth spot with what he had been showing, especially his solid outing against Team USA on Wednesday night.
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"I'm here competing for a spot, and I thought I made a statement that I'm supposed to be throwing in that capacity as a starter," May said. "That vision I had for this season was starting to manifest itself. That makes the blow a little bit harder to take."
May said he felt something grab in his elbow while pitching against Andrew McCutchen and Team USA on Wednesday. An MRI exam revealed the tear.
"When the results of the MRI came back, it was a little bit unique in the sense that it sounded as if the wear and tear component, or the cumulative impact, was very minimal," Levine said. "It really was an acute injury."
With May potentially out for the season, it gives right-hander Jose Berrios a leg up on the competition to be the fifth starter. Berrios is competing with Tyler Duffey, Ryan Vogelsong and Adalberto Mejia.
"I don't think you ever have any misgivings that you're going to go through the process without needing significantly more than five starters," Levine said. "You hate to have it happen at this point to a player who's put in the work that he's put in, but the reality is that's why we built up some of the depth we did coming into camp, and it's going to give other guys opportunities."