Replacing debuting starter Henry Owens, Robbie Ross Jr. gave up two damaging hits in just three pitches in the sixth, as the Yankees tied the game and then swiftly took the lead.
Jean Machi got just one out while giving up a hit, a walk and three runs.
Lefty Craig Breslow recorded two outs while giving up four hits and five runs.
Alexi Ogando gave up a three-run homer on the first pitch he threw.
The Yankees scored nine runs in the seventh against Boston's beleaguered relievers.
"Well, every guy that we brought to the mound, some pitches found the middle of the plate and they didn't miss them," said Farrell. "A nine-run inning, that's a rough night. Obviously, we're looking for better. Their lineup had their way with our bullpen."
Though Junichi Tazawa and Koji Uehara continue to be mostly effective as a 1-2 punch, the rest of the bullpen has been out of sorts.
It would stand to reason that Farrell might try some new faces out there soon.
"I'm not going to rule it out," said Farrell. "To answer that with specific names at this point is probably a little premature, but you're looking for better. You're looking for more. Particularly with guys that have had some stretches of success this season, that was a rough night tonight."