FORT MYERS, FLA. -- Rafael Perez underwent an arthroscopic debridement of the left shoulder on Sept. 26. I'm sure most of you have that one, but for the few that aren't sure, the Internet says debridement is the removal of tissue damaged by arthrosis, rheumatoid arthritis, by overuse, or by other means.

In the case of Perez, Doc Reusse here is going with "overuse" as the cause. Perez came to the Cleveland Indians to stay on May 28, 2007, and was the primary -- and on occasion the only -- lefthander in the bullpen through the 2011 season. Counting a shift in Class AAA Columbus in 2009, Perez hit 70 appearances in each of the four seasons from 2008 through 2011.

Cleveland intened to get a similar workload in 2012, until Perez started experienced shoulder soreness in spring training. He made eight appearances in April, went on the disabled list on April 26 and didn't pitch again until a rehab assignment to Columbus in mid-July.

Perez had to shut it down, pitched once more for Columbus on Aug. 11, sprained an ankle and that was it for the season.

"No one was sure what was wrong," Perez said. "I kept trying to rehab."

Finally, it was determined that Perez needed surgery -- the removal of a small piece of bone and some tissue from behind the shoulder. Two months after the surgery, Perez, 30, was designated for assignment by the Indians. No team was interested in making a trade. He waited until Feb. 14 to get a minor league contract with the Twins.

The Twins talked about building up Perez' arm to the point that being a starter was a possibility. That's what he was for the Indians organization from 2002 to 2007. Then, he came to the Indians and was put in the bullpen to take advantage of the slider that he could snap off against lefthanded hitters.

Perez came to Twins camp and tried to get cranked up quickly. There was discomfort and the Twins backed him off. He had a long-toss session on Thursday. There's no timeline for Perez to pitch competitively. He figures to be down here for extended spring training when the four full-season minor league teams start their schedules on April 4.

Perez was interrupted from an iPad game he was involved with on Thursday morning for a brief conversation. He said the shoulder has been good the past few days.

"When do you think you will be throwing sliders again?" he was asked, more in jest than as an inquiry.

Perez smiled at the mention of the weapon that made him so unpopular with Twins' lefties Joe Mauer and Justin Morneau. "When I came in this clubhouse, they both told me, 'We're happy to have you here, Rafael, and not in Cleveland,' " Perez said.

Morneau has more at-bats vs. Perez than any hitter with 19. He's 4 for 19, with a double, four RBIs, two walks and only one strikeout. Mauer is 3 for 12, with a double, one RBI, two walks and two strikeouts. It was more a lack of comfort for the lefties against Perez' slider than abysmal results.

Similarly, I asked Tony Oliva about Perez' slider, and it led him to naming "Hamilton, the big guy from the Yankees" as the lefty reliever that made him the most uncomfortable.

That would be Steve Hamilton, a 6-6 lefthander who was a presence in the Yankees' bullpen for much of Oliva's career with the Twins.

"I would stand close to the plate against him, to protect against the slider," Oliva said. "And if I got a pitch early in the count, I would swing."

To excellent result: Oliva went 8 for 18, with four doubles, six RBIs and three strikeouts against the lefty reliever with the slider that he disliked the most.