Yankees manager Aaron Boone said Warren was shut down last week due to a sore right shoulder, Marly Rivera of ESPN.com reports. Warren is expected to remain sidelined for a week before potentially resuming a throwing program.
The Yankees had already reassigned Warren to minor-league camp over the weekend, ending his bid for winning a spot in the club's Opening Day bullpen. Assuming Warren doesn't request his release from the Yankees, he'll turn his focus to getting healthy in advance of Triple-A Scranton-Wilkes Barre's season, which begins in May.