24. Mark MelanconPrevious ranking: 10
Acquired from the Astros in a December deal that sent Jed Lowrie and Kyle Weiland to Houston, Melancon was such a disaster in the season's early weeks (49.50 ERA, 11 earned runs in two innings) that he was exiled to Pawtucket. But Melancon found his form and his slider in Triple A, and has allowed just a run in six innings since returning. He'll likely contribute more than Daniel Bard this year.