The Phillies activated Halladay from the DL to start in place of Tyler Cloyd, who had to pitch five innings in Philadelphia's 18-inning loss to the D-backs on Saturday. Halladay had been on the disabled list for three months after right shoulder surgery.
"There's nothing different, which is good after pitching in Philly rather than Reading -- a little bit more adrenaline, Major League game," Sandberg said. "He didn't stress himself, that's good. He was under control, and feels really good today."
Before Sunday's game, Halladay made two rehab starts with the rookie-level Gulf Coast League Phillies and Class A Lakewood.
Sandberg said Halladay will remain in Philadelphia's rotation.
Chris Iseman is an associate reporter for MLB.com.