CLEVELAND – Tyler Duffey's demotion to the Twins bullpen lasted one day, and didn't involve any actual relief appearances.

The righthander was restored to the Twins rotation Monday after lefthander Fernando Abad was traded to Boston. Manager Paul Molitor decided that with the increased likelihood that Taylor Rogers or perhaps Buddy Boshers might be needed for late-inning work that once went to Abad, he needed another lefthander in the bullpen.

That lefthander will be Tommy Milone, at least for now. Milone was informed of the change Monday, and Duffey, who has recorded only 11 outs combined in his past two starts while allowing 11 runs, was restored to the rotation. He will take his normal turn on Wednesday, and newcomer Hector Santiago, a lefthander to replace Milone, will make his Twins debut on Thursday.

"Tommy's going out there to give me some length," and not to fill Abad's old role, Molitor said. "I'm going to have to move some other people around, mix-and-match that eighth inning [role] for now."

Molitor said he's inclined to use either Rogers or righthander Ryan Pressly in the eighth inning to set up closer Brandon Kintzler, but he's not ready to commit to either one in that job full-time. He also has Trevor May for late-inning work.

Buxton's knee is OK

Byron Buxton told the Twins athletic training staff that he heard a pop in his right knee as he approached second base during a steal attempt on Sunday, which is why he didn't slide. So the team was relieved Monday when a magnetic resonance imaging test turned up no structural damage in the knee, just some lingering bruises from the series of collisions he has had with outfield fences lately.

"He aggravated [the bruising] somewhat peculiarly just by running," Molitor said. "It prevented him from going into a slide. But we're fairly optimistic he's going to be available in the short term. I'm hoping it's only a day-to-day thing."

Buxton flew to Cleveland after his MRI, arriving at Progressive Field just before the game's first pitch.

Sano sits again

For the third time in five days, Miguel Sano was left off Molitor's lineup card, an indication, the manager said, that he is trying to find a solution to the young third baseman's ongoing problems.

"I'm trying to get him back on track," Molitor said. "We're trying to get him a little more confident on both sides of the ball right now."

Sano committed 11 errors at third base in July, after returning from a strained hamstring that kept him on the disabled list in June. He's also committed a couple of costly base­running gaffes, and has struck out 13 times with no walks in his past 23 plate appearances. His slugging percentage is off 80 points from his rookie season, and his on-base percentage is down 50 points.