Teams in need of bullpen help certainly won't be lacking in options during the coming weeks.
Per MLB Network insider Ken Rosenthal, the reliever market is expected to be especially heavy on mid-level arms, creating a buyer's market.
Sellers will need to keep their demands realistic and be aggressive, as the Rays and Royals did when they traded Alex Colome and Kelvin Herrera, respectively, earlier this month.
Rosenthal mentions the Orioles, White Sox, Reds, Tigers, Marlins, Mets, Padres, Rangers and Blue Jays as clubs that are expected to be selling relievers, and the Astros, Indians, Angels and Braves among the contenders likely to be in the market for bullpen arms.
The following relievers are among those reported to be available:
Orioles:Zach Britton, Brad Brach, Darren O'Day
White Sox:Joakim Soria, Xavier Cedeno
Reds:Raisel Iglesias, David Hernandez, Jared Hughes
Tigers:Shane Greene
Marlins:Kyle Barraclough, Adam Conley, Brad Ziegler
Mets:Jeurys Familia
Padres: Brad Hand, Craig Stammen, Kirby Yates
Rangers:Jake Diekman, Keone Kela
Blue Jays:John Axford, Tyler Clippard, Seunghwan Oh, Aaron Loup
While Hand, Iglesias, Britton and Familia stand out as high-end options, the others on that list are likely to be viewed as having similar value by clubs looking to upgrade their relief corps.

The list of teams selling relievers may only grow as July 31 draws closer, and some of the names above will likely still be available in August.