It may come as early as the first game of the season, but it will assuredly happen, and happen repeatedly: The Twins will win or lose games based on the ability of the bullpen to get a tough right-handed hitter out with men on base in the sixth or seventh innings.
They won't be using Joe Nathan or Matt Capps that early. Nor are they going to turn to Jose Mijares to get the likes of Jose Batista, Miguel Cabrera or Paul Konerko in such situations.
I've labeled the pitcher who will be entrusted with such at-bats as "set-up2/middle relief 1" in my various versions of COPOP -- Current Outsider Projected Opening Pen. Having somebody good for such a role is a sure sign of a deep and effective bullpen. In recent seasons the role has been filled by such worthies as Jesse Crain and Pat Neshek. Both are gone.
I'm currently anticipating that Jim Hoey will get the first shot at the role. He throws hard, but his control record falls short of Twins standards. Aaron Gleeman thinks Jeff Manship is more likely to make the 25-man roster than Hoey, but I just cannot see Ron Gardenhire entrusting big at-bats to his relatively mediocre stuff, at least not until he's paid a few more dues. He may be Matt Guerrier 2.0, but the first Guerrier didn't get this kind of role for a couple of years.
Kyle Waldrop won't be on the opening roster, and even if he was, he (and Hoey) would have the same unproven label to contend with.
Which would seem to point at Kevin Slowey for that role. Gardenhire has said the displaced starter would be asked to get big outs. I'd rather see Hoey, or Waldrop, get that opportunity first.