CLEVELAND -- The right elbow flexor muscle strain that landed Joe Nathan on the disabled list is Grade 1, the most mild version, Nathan said Friday. Still, it's serious enough that he won't be picking up a baseball until the tightness is gone, at least a week.
"We're going to do the right thing," Nathan said. "We'll give hopefully about a week of no touching a baseball and hopefully allow this thing to calm down, but we will definitely make sure we don't touch anything until there's no discomfort."
The injury, Nathan said, dates back to his final outing of Spring Training, which lasted one batter and seven pitches in the Tigers' finale against the Rays last Saturday. He tried to pitch through it, but felt it worsen in his Opening Day save against the Twins. Both outings were short, but both presented issues for him.
"Warming up, I felt fine," Nathan said, "but when I started amping up felt it a little bit. The first pitch to Torii Hunter is when I really felt it. And then from there, it just got tighter and tighter.
"I think the positive thing for me is I was still locating, velocity was still there, so fortunately I think we at least caught this before something major could happen. But it did feel like it was so tight, especially as the night progressed, if I did continue to push -- I tried to play catch the next day and it was one of those things I knew I couldn't throw in a game -- I think if I pushed through a game, I might have done something worse, might have torn something or something like that. So I think we caught it early enough. Twenty-four hours later, it already felt like it was calming down."
The first pitch Nathan threw was a slider, as were his final two, leading to a game-ending strikeout with the potential tying run on-deck. However, Nathan said, his ulnar collateral ligament checked out fine, and the injury felt different than the one that led to Tommy John surgery for him in 2010.
"If you're asking me my opinion, I don't think how much weight you can take with it," Nathan said. "But I think [the move] is just kind of protective -- that little twinge I felt in the spring and kind of overworked myself when I was out there."
Joakim Soria will close games for Detroit while Nathan is out.
Jason Beck is a reporter for MLB.com. Read Beck's Blog and follow him on Twitter @beckjason. This story was not subject to the approval of Major League Baseball or its clubs.