SAN DIEGO -- The Padres’ climb to the postseason grew a bit steeper on Friday, with news that they’ll be without frontline starting pitcher Joe Musgrove for the foreseeable future.

The right-hander will be shut down from throwing for at least three weeks after tests revealed inflammation in his right shoulder capsule. General manager A.J. Preller did not rule out a 2023 return for Musgrove and said doctors have indicated surgery isn’t likely. But Preller added there won’t be any true indication of Musgrove’s next step until he undergoes further examination after his rest period.

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On Wednesday, Musgrove was scratched from his scheduled start with what the team called “minor” shoulder soreness. He subsequently flew to San Diego for imaging, which revealed the injury.

“I honestly thought we were going in for a pretty routine checkup … but they went in and found some injury to the capsule,” Musgrove said. “Every part of me wants to go out there and throw. But everything’s telling us that we needed to step back and give it some rest.”

It’s a blow to the Padres’ playoff chances. Musgrove has a 3.05 ERA in 17 starts this season, including a dominant two-month stretch in which he owns a 1.88 mark since the start of June.

At the very least, the Padres can fall back on the fact that they reinforced their rotation at the Trade Deadline, adding left-hander Rich Hill in a deal with Pittsburgh. They also fortified their bullpen with a trade for Scott Barlow that could allow Nick Martinez to build back toward a starter’s workload.

“Injuries are never easy,” Preller said. “But we do feel like with Rich, with Michael Wacha coming back, Nick Martinez having some flexibility, Pedro Avila stepping up and throwing well … we’ve got some depth. And we’re going to use it.”

To that end, the circumstances are different from 2021, when the Padres passed on adding rotation help at the Deadline and then saw their thin group of starters ravaged by injuries shortly thereafter.

Still, Friday’s news sure tempers some recent optimism. The Padres were aggressive at the Deadline. They entered a home series against the Dodgers with five wins in their past six games. They moved within four games in the NL Wild Card race -- as close as they’ve been to a playoff spot since mid-June.

“We got the guys to do it," Musgrove said. “I don't think they're feeling out of this thing now that I'm injured. ... They haven’t lost sight of the goal. My job is to just crush this rehab and get back as soon as I can.”

Despite the gaudy numbers, it has been a frustrating season for Musgrove. He fractured his left big toe during Spring Training when he dropped a kettlebell on it in the team’s weight room. As he neared a return, he injured the AC joint in his shoulder after landing on it following an awkward throw to first base. Musgrove has also dealt with elbow bursitis and pitched through it.

It’s worth wondering if any, or all, of the injuries are related. Musgrove didn’t dismiss the possibility. But he noted that he’s felt mostly great recently. Sure, he’d felt some aches and pains, but they weren’t atypical to what he usually feels during a season.

But after his start on July 28, Musgrove noticed his shoulder wasn’t bouncing back the way it usually does. That’s when the Padres pressed pause. Musgrove didn’t throw his bullpen session, and he was scratched from his start. Once tests revealed the capsule issue, Musgrove consulted with a trio of doctors, who recommended rest, then a reevaluation.

“Extremely frustrating," Musgrove said. “But, you know, I could sit here and sulk and ‘poor me.’ Or I can take it for what it is … and try to be here for these guys as much as I can.”

In the meantime, the Padres have options. Hill is slated to make his Padres debut Sunday, manager Bob Melvin said. Wacha makes a Minor League rehab start on Saturday with Triple-A El Paso, which could line him up to return next weekend in Arizona.

“Look, that’s why you have some depth,” Melvin said. “Rich Hill’s here. We have Michael Wacha hopefully back, as well. You push forward. But, obviously, losing a guy like Joe, with what he means to this team, in many different ways, is one that stings.”