One of the relievers most widely expected to be traded this year has, indeed, been traded. The Padres have picked up resurgent righty Trevor Rosenthal from the Royals in exchange for young outfielder Edward Olivares and a PTBNL. That latter part is not necessarily nothing, recall, because all players not on a 60-man roster would have to be PTBNLs in order to be traded. So it could be a non-zero prospect.
As for Olivares, the 24-year-old has gotten a cup this year after hitting well at AA last year (it’s tough figuring out development tracks this year for other organizations, too), and he’s done little with it. He’s really still more of a prospect, and was right around the top 30 in a very good farm system. All things considered, that’s a strong get for the Royals in this environment, especially for a reliever who hasn’t had a lot of time to establish that he’s definitely “back.”
We haven’t had a lot of data points yet on the rental reliever market, where you’re most likely to see teams be aggressive (bullpens always need help, and if you get the right guy, he can be disproportionately valuable in the postseason). The Brandon Workman trade was pretty meh on the return side, but this one looks pretty strong, especially if the PTBNL is a decent prospect (though it might be conditional on the season completing). Something to keep in mind as you consider Cubs relief targets over the next two days.