|Brian Duensing has|
had the best
ratio of his career
so far this season.
Duensing, of course, has twice before opened the season in the bullpen for the Twins and finished the year in the rotation. When he opened 2011 in the rotation, he had a terrible time retiring right-handed hitters, which is why he lost his starting job.
The platoon differential has not been an issue this year for Duensing; while he's been devastating against lefties out of the bullpen this season, he's held right-handers to a .645 OPS. They've gotten singles off him, but just four extra-base hits, all doubles.
This may be a temporary gig; when P.J. Walters went on the DL the word was that he expected to be back as soon as the 15 days was over, and if that's the case, he'll be available before the fifth starter's spot comes up again. (But there is a make-up doubleheader a week from today, so the team is going to need a sixth starter as a result.)
On the other hand, it's not like the Twins have been getting such strong starting pitching that they would, or should, be quick to dismiss a good outing from Duensing. Much of his good relief work has been wasted this season because the starters have so consistently put the team in a big hole early. A decent starter is more valuable than a good reliever.
Still: Moving Duensing out of the bullpen permanently would leave the Twins with one left-handed reliever, Glen Perkins, and he's not going to be used as a LOOGY. I don't see a lefty reliever in the upper minors who deserves a shot at the job. It's not the best reason to keep Duensing in the bullpen, but it's probably going to be a factor.