Mike Adams (bullpen session) and Jonathan Pettibone (live batting-practice session) also are scheduled to throw tomorrow.
"All three of those guys are progressing," Sandberg said following yesterday's 8-1 loss to the Braves. "We are positive going into [tomorrow]."
Hamels entered camp saying he was "8 to 10 days" behind the rest of the pitchers after battling biceps tendinitis in November. He had been progressing without issue until last Thursday, when he was scheduled to face hitters for the first time this spring in a live batting-practice session but was unable to do so because he felt fatigued following his most recent bullpen session.
"I believe I threw 35 pitches - to my body, it felt like a thousand," Hamels said of his second bullpen session this spring, on March 1.
But 6 days after slowing his spring program, Hamels will return to the mound tomorrow and reboot his rehab. As long as Hamels progresses without another setback - which isn't a given - there is a chance he could get into a Grapefruit League game within 2 weeks.
Hamels isn't likely to be ready for at least the first 2 weeks of the season. With 2 days off in the 8 days of the season, the Phillies do not need a fifth starter until April 13.
The Phillies are far from the only team in baseball dealing with pitching injury woes this spring.
Among their National League East rivals, Washington righthander Doug Fister was scratched Friday with elbow inflammation, the Mets' Jonathon Niese (shoulder) will make his first start today, 2 weeks into the exhibition schedule, and the Braves have seen two starters leave early on back-to-back days. After watching projected Opening Day starter Kris Medlen grab his pitching elbow and leave on Sunday with what was diagnosed as a forearm strain, Atlanta manager Fredi Gonzalez had to take Brandon Beachy out of yesterday's game against the Phillies after two innings with elbow tightness. Beachy had been scheduled to pitch four innings.
"Thank God that we signed Freddy Garcia this winter," Gonzalez said before yesterday's game. He was asked about the progressions of Garcia and fellow ex-Phillie Gavin Floyd, given his sudden need for pitching depth.
"You just never know. You feel like you have enough [depth] and the next thing you know something happens and it screws up everything," Gonzalez said. "Everyone has injuries. The [teams] that can survive those injuries, or can hang in there, they're going to be in there at the end. Last year we lost [Tim] Hudson with that freak play at first base and our young kids stepped up . . . You think you're prepared, but you don't know."
David Buchanan will make his third appearance and second start when the Phillies visit the Braves in Lake Buena Vista, Fla., this afternoon. Buchanan, 24, has allowed two hits and one run in three innings while striking out three and walking none. He is among the starters suddenly competing for a possible fifth starter's job, with Cole Hamels, Jonathan Pettibone and Ethan Martin all slowed with injuries . . . The Braves scored five runs while Jonathan Papelbon was on the mound in the seventh inning. But all five were unearned: Third baseman Maikel Franco made a throwing error to begin the inning . . . Hard-throwing reliever Ken Giles struck out three of the five Braves he faced in the eighth inning. Giles, 23, has never pitched above Class A. Justin De Fratus also threw a scoreless inning of relief.
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