Duensing, who has made 50 career starts, has been impressive in 28 1/3 innings, primarily as the seventh-inning arm out of the bullpen, with a 2.86 ERA, 18 strikeouts and seven walks.
"We like Duensing where he's at," Twins manager Ron Gardenhire said. "He's eating up a lot of innings out there, getting people out. He's doing really, really well. There's a reason we took him out of that rotation; we wanted to see how he did in this role and see if we could strengthen our bullpen.
"If we have to put him out there we can do it, but right now he's doing pretty good where he's at, and when you find a niche for somebody, you stay with it for a while and see what happens."
The Twins have used nine starters already this season, and there's a good chance they'll use a 10th on Wednesday with right-hander Carl Pavano likely to hit the disabled list.
Gardenhire, though, said he'd rather use right-hander Jeff Manship in a spot start, as he's fully stretched out. Gardenhire didn't rule out using Duensing as a starter this season, but said it's tough to build up his pitch count enough to start.
"I can go to him, but one thing with Duensing, I'll have to stretch him out somewhere, and to do that you want to start him and pitch him three innings, and then go five innings," Gardenhire said. "I can't do that. It's pretty tough. Plus, I have [Glen] Perkins as my eighth-inning guy. If I start Duensing, I'm going to have to bring somebody up to take his spot in the bullpen, because I need another lefty out there."
One reason for Duensing's success this season has been his ability to get right-handers out. A year after right-handers posted a .947 OPS against him, right-handers have a .661 OPS against him this year.
"I've been able to get in on righties this year, which has helped," Duensing said. "I just seem to have confidence in everything this year. Everything's moving down, everything's working right now."