Phillies manager Ryne Sandberg said before Wednesday's game that Billingsley has been making progress and is working toward a return.
"He's on a throwing program," Sandberg said. "He threw from 75 feet yesterday and he'll continue to throw. [He's] playing catch basically. We'll lengthen that out day to day and it looks like right now that he'll do an actual side [session] on Tuesday on the road trip.
"He's building toward that. He's progressing really well and we're taking it on the slow side of things. Building up to the side on Tuesday."
Nick Suss is an associate reporter for MLB.com This story was not subject to the approval of Major League Baseball or its clubs.