The Yankees designated Hartlieb for assignment Wednesday.
Hartlieb will give up his spot on the 40-man roster and 26-man active roster to right-hander Cam Schlittler, who was called up from Triple-A Scranton/Wilkes-Barre to start Wednesday's game against the Mariners. Hartlieb has made two appearances out of the Yankees bullpen this season, giving up six earned runs in 1.1 innings.