Route #2: Half-measures that could bring substantial results
The second route they could take isn't as flashy, and at least in the short-term, has far greater risk to it, but is a route I could see them going down even more than I do them making a trade for a starter.
This route centers around them finally giving Michael McGreevy a full-time spot in their rotation, replacing one of Miles Mikolas or Erick Fedde, and then seeing how things play out down the stretch with their rotation rather than adding a new arm to the mix.
Depending on who you ask, this may be some fans' most preferred route for them to go down. First, it gets McGreevy into the rotation, which we all want to see, and it means the Cardinals are parting ways with at least one of Mikolas or Fedde, another potential win for the rotation. It also means the Cardinals are not blocking one of their other young arms from getting a chance to make starts, so there would be a world where Mathews, Roby, or another young arm gets the ball for St. Louis at some point this season.
The risk this route presents is the even shallower pool of pitching depth, but let's be honest, at this point in the season, there is no good arguement in my eyes as to how that means the Cardinals should hold onto terrible options like Mikolas or Fedde. They need better production out of those rotation spots, and if they somehow experience multiple injuries to their starters between now and the end of the season, well, the season would be going south with or without Fedde and Mikolas anyway.
Even just McGreevy's addition to the rotation over Fedde or Mikolas would make a difference. While no one should expect McGreevy to be a top-end starter the rest of the year, I do think he provides more stability and value than those two have as of late. I'll get into this later, but while Mikolas and Fedde were both fine on paper for the start of the season, their underlying metrics have finally caught up to them.
McGreevy, on the other hand, looks to be the kind of guy who can actually maintain solid back-end of the rotation production. Right now, Mikolas and Fedde both are unplayable. They aren't even giving the Cardinals a chance to win when they start. One of those types of players in a rotation is already bad enough, but two can destroy a team.
If Mathews or Roby is ready at some point as well, they could slot into the rotation and provide more upside as well, or may be called upon if injuries happen.