Velasquez will take left-hander Adam Morgan's spot in the rotation. Morgan will be available to pitch out of the bullpen Sunday, and his fate will be determined after that. Mackanin said Morgan could remain in the Phillies' bullpen.
"We're not sure we're going to do that," Mackanin said. "It's an option we're mulling."
Todd Zolecki has covered the Phillies since 2003, and for MLB.com since 2009. Read his Phillies blog The Zo Zone, follow him on Twitter and listen to his podcast. This story was not subject to the approval of Major League Baseball or its clubs.