BOSTON -- Right-handed reliever Lester Oliveros is likely out for the season, as he's scheduled to have bone chips removed from his right shoulder, Twins assistant general manager Rob Antony said Friday.

Oliveros, who was at Triple-A Rochester, has been plagued by elbow issues this season and will have the surgery at some point in the next two weeks. The recovery time is about 10-12 weeks, according to Antony.

"He came back and was throwing the ball well but it was barking on him," Antony said. "But this is one where rather than have him go through the year with it, we just want him to take care of it now. Our goal is to get him healthy by the end of the year. I don't think we'll be looking at winter ball. If we do, just the second half to get ready for Spring Training."

Oliveros, 24, posted a combined 2.42 ERA with 51 strikeouts in 48 1/3 innings split between Double-A New Britain and Triple-A Rochester this season. He also made one appearance for the Twins, giving up one run in 1 2/3 innings against the Phillies on June 14.

"He had some pretty good stretches there," Antony said. "It's disappointing, he could have been a guy that, if he had been healthy, he could have been a guy that could have been up here and had a chance to pitch out of the bullpen. He was throwing the ball very well."

Plouffe not expected to rejoin Twins on road trip

BOSTON -- Third baseman Trevor Plouffe's bruised right thumb still bothered him while taking swings on Thursday, so he's unlikely to rejoin the Twins on their road trip that ends on Wednesday in Cleveland.

Plouffe, who is on the disabled list retroactive to July 21, is eligible to return from the DL on Sunday. He originally injured his thumb when he was jammed by a pitch against the Royals on July 20.

"I don't know how comfortable he was swinging the bat [Thursday]," assistant general manager Rob Antony said. "I think there's still some soreness, but I would doubt he'll join us in Cleveland. That's uncertain, but probably not as optimistic as we were a day ago. Until he can swing without any pain in that thumb, I don't think he'll be rejoining us."

There's also a chance that Plouffe will go on a rehab assignment once he feels more comfortable swinging the bat without pain.

Quartet of injured pitchers making progress

BOSTON -- Twins assistant general manager Rob Antony gave an update on Friday on the four Twins pitchers on the disabled list.

Right-hander P.J. Walters, who has been on the DL since June 14 with right shoulder inflammation, is set to make a rehab start with Triple-A Rochester on Saturday.

Fellow righty Carl Pavano is on track to make his first rehab start on Tuesday in the Gulf Coast League. He's been on the DL since June 4 with right rotator cuff weakness.

"There is no date to get him back here," Antony said. "I think we're looking at, if all things go well, he may start a game on Aug. 7 in the GCL. His last couple bullpens felt good, his shoulder felt stronger and he's more comfortable."

Closer Matt Capps, on the DL with right rotator cuff irritation dating back to July 17, still hasn't thrown a baseball. He's working on strengthening his shoulder before he starts his throwing program.

"I think he'll be back pitching for us this year," Antony said. "Same thing as Pavano right now, he has to get his strength back, he has to be comfortable, and then when he does, he'll start throwing again."

And right-hander Anthony Swarzak has also yet to throw a baseball since being placed on the DL, retroactive to July 25, with a mild right rotator cuff strain. But he's making progress, according to Antony, and will play catch for the first time Saturday.