The lefthander says he isn't sure if he will throw another batting practice session before facing hitters in a game.
Hamels is expected to return about May 1, but he said if he continues to feel good, that timetable could be moved up.
Leftfielder Domonic Brown, who had not played since March 15, returned to the lineup and was the designated hitter in Saturday's 5-3 loss to the host Pittsburgh Pirates.
Brown missed time with the flu, and there was also an off-day and a rainout in the last week.
"I felt all right after eight days of not playing," said Brown, who was 0 for 3 with a strikeout and a walk.
A.J. Burnett allowed two earned runs in 51/3 innings, walking six and striking out two against his former Pirates teammates. He said his trademark curveball isn't where he wants it yet, but he feels it will come.
Having Carlos Ruiz catching was key, according to Burnett. The two haven't worked together since his first outing, a two-inning stint on March 2.
"It was good for him to see what I can do and good for me to know what he expects," Burnett said.
Trimming the roster
The Phillies assigned third baseman Maikel Franco, righthander Sean O'Sullivan, and outfielder Clete Thomas to minor-league camp.
Jonathan Pettibone (shoulder inflammation) pitched three scoreless innings in a minor-league game Saturday. It was his first game action of the spring, and he expects to pitch in Thursday's Grapefruit League finale. . . . Mike Adams (shoulder surgery) struck out two in a minor-league inning. His fastball sat at 90 m.p.h. Adams is slated to pitch Tuesday against the Yankees.
Matt Gelb contributed to this article.