The Yankees already had good pitching this season and made it even better at the trade deadline.
Sending four prospects to the Athletics netted starter Frankie Montas and veteran bullpen arm Lou Trivino. Sending another to the Cubs netted potential diamond in the rough Scott Effross. Not to mention they also boosted the outfield with Andrew Benintendi, and will boost it further with whatever Brian Cashman decides to do with Joey Gallo.
The pitching addresses a borderline desperate need for the Yankees. Injuries have the bullpen practically threadbare and both Trivino and Effross plug some significant holes.