Tyler Duffey will make his major league debut Wednesday for the Twins, taking the place of Tommy Milone, who is being put on the 15-day disabled list because of a flexor strain in his left elbow.

The 24-year-old Duffey, 4-6 with a 2.72 ERA at Class AAA Rochester, will face a Blue Jays lineup featuring Josh Donaldson, Jose Bautista and newly acquired Troy Tulowitzki.

"Big, strong, righthanded guy," Twins manager Paul Molitor said of Duffey on Sunday. "Velocity numbers are above average. He's got a breaking ball that's very effective against righties and lefties. When we saw him this spring, command was a little bit of an issue … [but] he's gone down and he's had a really consistent year."

The Twins discussed a few options, including Jose Berrios, but believed Duffey was more prepared.

"We think, where he's at, he's a guy we don't think is going to be intimidated or fearful of challenging a major league lineup," Molitor said. " … It's a little bit of a tough first start, we know that, given their lineup. But hopefully he responds to it."

Molitor called Milone's DL stint precautionary, adding that the lefthander hasn't had any elbow issues and tests have showed he is structurally "in good shape" but shows some signs of a strain.

"To back him off now makes sense," Molitor said.

As for Trevor May, who was moved from the rotation to the bullpen last month when Ervin Santana's suspension ended, he remains in a relief role and pitched a scoreless inning for the second day in a row Sunday.

"We talked about the possibility of doing something there, but it's starting to get to a point now, as far as length of time on the rotation, where we thought the amount of pitches he could give us would have been minimal," Molitor said.

Losing debut

Kevin Jepsen made his Twins debut and took the loss in Seattle's 4-1 victory after walking the first two batters he faced in the 11th inning. He came back to strike out Nelson Cruz before being pulled for Brian Duensing, who gave up the go-ahead RBI double to Logan Morrison.

"As much as you want your first impression to be a good one, it's nice to get out there and get that out of the way," Jepsen said. " … All in all, I felt like my stuff was fine. I just had a lack of control to start the inning."

The righthander was acquired Friday from Tampa Bay for two minor league pitchers. Jepsen appeared in 46 games for the Rays this season, posting a 2.81 ERA with 34 strikeouts in 41 ⅔ innings. The 31-year-old has spent parts of eight seasons in the majors.

"I'm just trying to take it all in," Jepsen said before the game. "Second day here in the clubhouse, so I'm just trying to get my feet wet. It's an emotional thing going from one team to another overnight. I've been tired the last couple of nights, enough to get plenty of sleep. Just worn out mentally … [But] it's been good. They've welcomed me with open arms."

Pelfrey sharp

Twins righthander Mike Pelfrey surrendered only four hits over eight shutout innings in what was his best start since his most recent victory June 7. Pelfrey said it was the first time in years he felt he didn't have to make a concerted effort to make the ball move and that the ball felt like it had a natural sink.

"I thought the slider was good today, and for the most part I thought I did a good job locating my fastball," Pelfrey said. " … Velocity was better than it has been since the break. So I felt good out there."