Halladay had to leave after Starlin Castro led off the fifth with a single. The right-hander bent over, drawing a visit from a trainer, and left with the Cubs leading 3-1.
He tried to stay hydrated. He used iced towels and changed his shirt, but he simply couldn't continue after Castro's hit. Halladay says he had never experienced anything like that, but he was feeling "a lot" better a day later and expects to make his scheduled start against San Diego on Sunday.
The Phillies also got good news about Roy Oswalt, who threw nearly 50 pitches in a pain-free bullpen session on Tuesday.