The Yankees recalled Warren from Triple-A Scranton/Wilkes-Barre on Wednesday.
He's taking the roster spot vacated by Luis Gil (back), who was placed on the 15-day injured list. Warren also seems likely to replace Gil in the rotation, although it's unclear when he might make a start. The rookie right-hander has not pitched since being optioned last Thursday, so he should be available to start at any time. Warren holds an 8.59 ERA and 17:5 K:BB over 14.2 innings covering three starts for the Yankees this season.