Recently, we learned that Tyler Chatwood took a turn for the worse in his rehab efforts. He's currently on the 10-day Injured List, but it sounds like a transfer to the longer (45-day) list might be justified. Doing that would end Chatwood’s season. If he’s transferred, it opens a few options, as well as questioning the wisdom of a recent roster decision.
The obvious move would be to activate Pedro Strop. He sounds ready to go, and could take Rex Brothers' spot on the active roster without much concern. Brothers still seems to be a low-leverage option, and low-leverage options with no future team control are of limited value in October.