OAKLAND, CALIF. - After missing seven games because of a sore clavicle/neck area, Twins outfielder Denard Span is being examined again.

Span had an magnetic resonance imaging exam of his neck on Monday, which came back negative. On Tuesday he will have an MRI of his right clavicle.

Span injured himself Aug. 12 trying to make a falling catch in center field. He thought he would be ready in a few days, but continues to feel discomfort.

The Twins still won't say he's a candidate for the disabled list, but they ordered the exams to make sure nothing more serious is bothering him.

"Basically we're doing that just to make sure we're not missing anything," Twins assistant general manager Rob Antony said. "We want to rule everything out and give him peace of mind."

Pitching switch The Twins aren't the only team in this series with plans to alter their pitching rotation.

Oakland is activating lefthander Brett Anderson from the disabled list to start Tuesday. Anderson has not thrown a pitch in the majors since June 5, 2011, because he tore the ulnar collateral ligament in his elbow and had Tommy John surgery.

In five rehab starts for Class AAA Sacramento, Anderson was 1-1 with a 4.62 ERA, walking just five batters in 25 1/3 innings.

Anderson, 24, is 21-23 in his career with a 3.66 ERA. Before the injury, he showed flashes of being a top-of-the-rotation starter.

Swarzak is back Righthander Anthony Swarzak pitched a scoreless inning Sunday in his first appearance since coming off of the 15-day disabled list because of shoulder soreness.

Swarzak filled various roles before he was injured, serving as a long and short reliever and even got a few starts. It will take a while, and a few outings, before the Twins are comfortable with him being so versatile again.

"I'm just glad he's healthy," Twins manager Ron Gardenhire said. "He's really never had any kind of arm problem, so we were concerned about that. But he bounced back just fine from it.

"The ball came out of his hand good. I was worried about him being a little rusty. We put him in a tighter game than we wanted to but we needed an inning and he got through it just fine.

"I don't think we're ready to stretch him out to four or five innings or anything like that --like he was before. But we'll kinda build into that maybe two to three innings and see how he's doing. We'll watch him early and go from there."

Etc. • Carl Pavano will skip his scheduled start Tuesday for Class A Fort Myers and instead fly to New York to have his shoulder examined by Dr. David Altchek. It sounds bad, but Pavano wanted to visit Altchek all along to make sure he was going about his rehabilitation properly. When he found out he could see Altchek on Tuesday, he was allowed to push his start back. Pavano has been plagued by shoulder weakness since the beginning of the season and has not pitched since June 1.

• Righthander P.J. Walters, also coming back from a sore shoulder, had no problems on Monday after throwing three scoreless innings Sunday.

• Oakland traded for shortstop Stephen Drew from Arizona for minor league infielder Sean Jamieson.