ANAHEIM -- Lance McCullers didn't suffer a setback in his rehab, but Astros manager AJ Hinch said Sunday the right-hander isn't progressing as much as the team would like.
Although McCullers was initially slated to throw off a mound as early as late August, the Astros will instead slow his rehab and won't have him work from a mound until at least early September. In the meantime, McCullers has been playing catch on flat ground.
"I don't think it's a setback as much as it is a sort of continued lack of progress to the speed in which it's OK to get on the mound," Hinch said. "We thought we could be a little more aggressive with him, but we're going to put him on pause and just have him do a throwing program. He's feeling pretty symptom-free. His throwing has been fine, but the re-evaluation of him, we've decided to push him back until September."
McCullers hit the 10-day disabled list Aug. 5 with what was initially feared to be a significant elbow injury, but it was later downgraded to a right forearm strain. His return has long been expected to come in September.
This season, McCullers has posted a 3.93 ERA and a career-high 138 strikeouts in 126 innings over 22 starts. However, it seems unlikely he'll be pitching as a starter when he returns.
"It would be hard to get him built back up as a starter," Hinch said. "I guess never say never, because once you get back on the mound and get going, things can progress a different way, but I think the focus will be, and probably should be, shorter stints."
McCullers has never appeared as a reliever in the regular season during his four-year MLB career (80 starts).
Worth noting
• George Springer wasn't in the Astros' lineup for a sixth straight game on Sunday, but he made a pinch-hitting appearance in the ninth inning of the Astros' 3-1 win over the Angels.
"He's never been more excited to get in a game and strike out," Hinch said.
It was Springer's first appearance in a game since Aug. 19 due to left quad soreness. Hinch said he expects the outfielder to return to the lineup on Monday in Houston.
"He was bouncing around today, even fighting to play a little bit more today," Hinch said. "Tomorrow, I'm expecting him to be in the lineup at home against Oakland."
• Jose Altuve was in the lineup Sunday despite taking a 99-mph fastball to his left elbow on Saturday. There's little doubt the second baseman is still in pain, but the Astros aren't concerned he sustained any damage beyond that.
"More times than not with Altuve, he's going to say 'I really want to play,' and we want to push him to play," Hinch said. "It's a muscle issue. You get hit, you're going to have a little bit of soreness, but he'll be fine."

• Jake Marisnick, Brian McCann and Chris Devenski are all expected to continue their rehab assignments after Saturday off. Marisnick will be playing center field with Triple-A Fresno, while McCann will DH and Devenski will pitch at least one inning for Double-A Corpus Christi.