Manager Charlie Manuel believes Moyer is headed for the 15-day disabled list, based on input from the team trainer. Moyer was scheduled to meet team physician Dr. Michael Cicotti on Thursday and the team made no move before Wednesday night's game against the St. Louis Cardinals.
Moyer's injury leaves the Phillies with rotation openings Saturday and Sunday. Phillies general manager Ruben Amaro Jr. said Tuesday he had a plan to replace Kyle Kendrick, who was optioned to Triple-A Lehigh Valley earlier this week.
Kendrick's next start would be Saturday and Moyer's would be Sunday.
Manuel also juggled his lineup, moving slumping leadoff man Jimmy Rollins to sixth. Rollins was 2 for 24 since the All-Star break and his average was down to .225.
Manuel believes Rollins' woes are related to his two stints on the 15-day disabled list for a calf injury.
"Jimmy's working on trying to find his swing and it's kind of like spring training for him," Manuel said. "He knows what he's doing. Sometimes you know what you're doing but it takes a while to get your swing down."
Earlier Wednesday, the Phillies optioned right-hander Andrew Carpenter to Triple-A Lehigh and purchased the contract of right-hander Vance Worley from Double-A Reading. Carpenter pitched two innings and took the loss Tuesday, and Manuel said Worley provided bullpen insurance for a team running short of arms.
"We had to send Carpenter back. That wasn't in our plans," Manuel said.
"I try not to let it bother me until we get right down to 'Hey, we've got a trade,' " Manuel said. "Until a guy shows up, that's when I know we have him."
Manuel said one top-notch starting pitcher could help turn around the Phillies, who had lost five of six out of the break.