Castro allowed one hit in a scoreless ninth inning against Boston on Sunday. He struck out two and picked up a save.
Castro coughed up a single but still closed out the 4-2 win with ease. He's converted five of his six save chances this season, including four straight dating back to May 12. During that span, Castro has fired 8.1 shutout frames, lowering his season ERA to 2.22 with a 22:8 K:BB.