CLEARWATER, Fla. - Roy Halladay threw his regular, in-between-starts bullpen session Wednesday while the vast majority of the Phillies enjoyed a rare day off.

It was the first time Halladay took the mound since departing his start Sunday with a stomach illness after just one inning. Halladay said he lost about 10 pounds as a result of the bug, which sapped him of energy and strength before he resumed baseball activities Tuesday.

On Wednesday, pitching coach Rich Dubee watched the two-time Cy Young Award winner's mound session.

"Roy threw very well," Dubee said through a team spokesman. "He lost almost 10 pounds, so he's got to gain some weight back and get his strength."

The Phillies are hoping Halladay progresses in the next two weeks; he likely would be slotted to follow Cole Hamels in the rotation once the regular season begins.

Halladay's progress this spring has been slowed in the last nine days, however.

First, he got knocked around against Detroit in a 2 2/3-inning start that left him feeling "lethargic." Then, Sunday, Halladay threw just 25 pitches before he became too ill to continue.

Halladay is next scheduled to throw in a minor league game Saturday at the Carpenter Complex in Clearwater. If he continues to progress, Halladay likely would be in line for March 28, the final day the Phils will spend in Clearwater before breaking camp and heading north.

That game (March 28 against the Toronto Blue Jays) would figure to be the only time Halladay will face major league hitters before the season begins.