For much of the first four months of the season, the Yankees had two of the three best left-handed relievers in baseball in their bullpen in Aroldis Chapman and Andrew Miller. Those two plus Zach Britton are the holy trinity of end-game southpaws. They’re not lefty specialists. They dominate batters on both sides of the plate.
After wisely trading away Chapman and Miller at the deadline, the Yankees picked up lefty Tommy Layne as soon as the Red Sox cut him loose. Boston acquired Fernando Abad at the trade deadline and didn’t need Layne anymore, so they flat out released him.