Update 3:20
The exact timing is a bit unsure, but we've learned the Tigers appear to be set to shake things up a bit in the rotation and bullpen with a couple of moves they'll be making during the next week or so. Left-handed starter Charlie Furbush, who allowed two runs in six innings Tuesday while striking out eight, will be brought up to Detroit to join the Tigers' bullpen. Left-handed starter Andy Oliver, who is on schedule to to pitch for Toledo Thursday, will join the Tigers rotation at some point soon, too. To make room, Phil Coke, tonight's scheduled starter in Boston, will be sent to shore up the bullpen.
Obviously last year Oliver struggled a bit in his first experience in the major leagues, finishing with an ERA of 7.36 in 22 innings, but that was also just his first year of pro ball. This year Oliver has a 2.89 ERA with the Mud Hens. This season he has struck out batters in 24.4% of plate appearances and walked them in 9.7%. His walks+hits per inning pitched (WHIP) is 1.26.
Furbush's stats headed into Tuesday: 2.90 ERA with 34.4% K/PA and 4.4% BB/PA. His WHIP was 0.893.
Corresponding moves will need to be made. I'm not sure what those are.
Speculation: Ryan Perry has not performed well this season, and he's sporting an ERA of 9. You could do worse than option him to Toledo. Or maybe Joaquin Benoit actually is injured. A left-handed reliever will have to be removed from the active roster as well or the bullpen will be flooded in them. It should be Brad Thomas, who just isn't getting the outs and is performing almost purely in a mop-up role because of that. But Daniel Schlereth hasn't pitched in a week either and seems to be a possibility for going down and up despite having a decent start to his season.
To me, it would make the most sense to skip Coke's start tonight, move him directly to the eighth inning, and call up Oliver before tomorrow's game. But I don't know that the Tigers are thinking the same way.
In any case, this might explain why Jim Leyland did not want to share his plans for the bullpen with the media yesterday.
Update: For those worried, Jacob Turner will stay in Double-A Erie. Chris Oxspring appears to have been released and has an opportunity in Taiwan if he wants it.