Benoit apparently injured himself on the stairs. He is 1-2 with a 3.68 ERA in 23 appearances. He had not allowed a run in his past eight appearances, dating to May 13. He had allowed two hits and two walks and struck out five.
The Phillies recalled left-hander Adam Morgan to take his place on the roster.
The Phillies also activated right-hander Ben Lively before Saturday's game against the Giants. They optioned right-hander Mark Leiter Jr. to make room for him.
Todd Zolecki has covered the Phillies since 2003, and for MLB.com since 2009. Follow him on Twitter and Facebook and listen to his podcast. This story was not subject to the approval of Major League Baseball or its clubs.