CINCINNATI - Twins closer Matt Capps hasn't been on the disabled list since 2008, but he appears headed there now after waking up with more pain in his right shoulder Sunday.

The Twins promoted lefthanded reliever Tyler Robertson from Class AAA Rochester, knowing they will likely have to fill Capps' roster spot. Robertson, 24, had a 3.77 ERA in 33 games for the Red Wings, and he will give the Twins a second lefthanded relief option along with Glen Perkins now that Brian Duensing has moved to the rotaton.

Though the roster move was not official, Twins assistant GM Rob Antony said, "All signs point to [Capps] going on the DL."

A shoulder issue kept Capps from pitching for seven days before he made a one-inning appearance Saturday. He expects to have a magnetic resonance imaging exam on Monday.

Capps, 28, is 1-4 with a 3.42 ERA and is 14-for-15 in save opportunities.

"It's been a bounceback year after what we dealt with last year," he said. "And I feel like this team is on the verge of turning things around, and it would be nice to be a part of it. But I've gotta find out what's going on with me."

Interim closer plans Manager Ron Gardenhire hasn't named an interim closer. He used lefthander Glen Perkins for two saves last week, but Sunday, with righthanded hitters due up in the ninth, he gave righthander Jared Burton a chance.

Burton walked two of the first three batters but escaped with his first career save. The lefthanded-hitting Joey Votto was waiting on deck when the game ended, and Gardenhire had Perkins ready, just in case.

"It was pretty intense, but never in doubt, right?" Burton said. "I had it the whole time."

Rotation plans The Twins will promote a pitcher from Rochester to pitch one of the games in Saturday's doubleheader against the Royals. Cole De Vries pitches Monday, so if he is promoted again, Saturday's start would come on regular rest, but another candidate is Sam Deduno, who allowed one hit in six shutout innings Friday for Rochester.

P.J. Walters (right shoulder inflammation) is eligible to return from the DL on Thursday, but the Twins want him to make at least one minor league rehab start before returning.

Etc. • With 38 players on their 40-man roster, the Twins have discussed using one spot to reacquire Mounds View High School grad Mark Hamburger, recently designated for assignment by the Rangers. The Twins traded him to Texas in 2008 for Eddie Guardado. Hamburger, 25, reached the big leagues last year but posted a 6.55 ERA in 21 games for Class AAA Round Rock this year.

• Righthander Carl Pavano (rotator cuff weakness) has regained strength and should be able to start a throwing program this week, Antony said.

• According to baseball-reference.com, the fifth-inning home run Trevor Plouffe hit Sunday was his first opposite-field homer since the first one of his career, which came Aug. 7, 2010. This one made Plouffe the new team leader with 15 home runs, though Josh Willingham tied him with his ninth-inning blast.