WEST SACRAMENTO, CALIF. − Pablo López has already started his rehab.

"I got a crazy lower-body workout in today already," the Twins' ace starter said Wednesday with a rueful smile. "I will find ways to stay healthy."

Too bad he couldn't do so a day earlier. López walked off the mound Tuesday, when he felt soreness in his shoulder, and on Wednesday he learned what that soreness meant: He has suffered a Grade 2 strain of the teres major, a muscle that attaches to the scapula (commonly known as the shoulder blade).

It's the same condition that Joe Ryan experienced last Aug. 7, and the prognosis is the same. It will take two or three months to heal, which was season-ending for Ryan, but gives López reasonable assurance that he will pitch again this season.

Like Ryan a year ago, the pain López feels doesn't seem nearly so serious.

"I hated it. I hated the idea yesterday, I hate it today. I'm going to hate every single second and day of it," said López, who was placed on the injured list Thursday. "I was hopeful, based on the things I felt, the way I was feeling this morning. I was like, 'It feels more like soreness really than anything.'"

But it's far more serious, and a serious blow to the Twins, too. They have the pitching depth to get through his absence but not many pitchers can equal López's 2.84 ERA.

"It's obviously not something that any of us want to see, Pablo first and all of us as well, but we're not sitting here having dire thoughts," manager Rocco Baldelli said. "We fully expect him to be back this year and pitching for us a good amount. We're going to stay optimistic and let him do his thing."

That thing won't include throwing a baseball, or even raising his right arm above his head, for the next month.

"I've got to wait a little bit for the discomfort to clear before I do overhead things," López said. "I'm going to be hitting the weight room hard for my legs, a lot of cardio, and whenever I get cleared to start things on my right arm, do that. But until then, I guess I will be a full-on lefty."

It still strikes him as odd that there's no pain shooting through his body, just a mild soreness.

"It feels like I did close to 10,000 lat pulldowns after not doing them for months. It's like a weird soreness, which is why I was hopeful early on. It just feels like it's sore," López said.

"Obviously, I put that in my head like, oh, it's probably going to be a great one because of that. Lo and behold, it wasn't. As soon as they told me it wasn't, I'm like, 'Oh, that soreness feels a little more uncomfortable now.' I was playing tricks on myself."

And it won't be easy not taking his turn every five days, he acknowledged.

"From today on is going to be more mental than physical. Like, I know physically, I am going to feel good. I am going to recover. I am going to feel strong," the 29-year-old López said.

"The mental side is what's going to be eating me alive for a while. It's just that itch, knowing that every day that passes is games I'm not participating in. So the options are simple.

"I either choose to drown myself in tears of sorrow, or I choose to power through, grow internally, externally, grow physically, grow emotionally, and just make sure that when the time comes, that I will be able to come back."