LOS ANGELES — The Padres have looked high and low and everywhere in between to squeeze more out of the rotation.

Now the strength of the team is taking a hit.

For the second time this season, reliever Jason Adam has landed on the 15-day injured list, this time with a shoulder strain that surfaced while throwing before Wednesday’s game in Chicago. The Padres activated right-hander Germán Márquez (forearm nerve) from the injured list to take Adam’s place on the active roster, but a relief corps assembled to shorten games is short on late-and-close arms.

Right-hander Jeremiah Estrada is already on the injured list for the second time this season with right knee inflammation and has yet to begin a rehab assignment. Right-hander David Morgan — who was expected to take a step forward this year — landed on the injured list earlier this week with knee inflammation. Adam began the year on the injured list as he built up following last year’s season-ending quad injury and will now have an MRI on an achy right shoulder.

That figures to put even more pressure on left-hander Adrian Morejón (3.32 ERA) to get a lead to closer Mason Miller (0.78 ERA). It’s also an opportunity for rookie right-hander Bradgley Rodriguez (2.06 ERA) and left-handers Wandy Peralta (1.62 ERA) and Yuki Matsui (1.53 ERA) to show that their success this year can translate to higher-leverage spots in a bullpen that has the fifth-best ERA (3.56) in the majors.

“It’s part of the game,” Morejón said. “One of the best relievers on the team is on the injured list right now. We need all the guys in the bullpen right now to stay focused and go compete every inning. Obviously me and Mason will try to help the team every time, especially most of the time I come in in the seventh or eighth inning. Mason is always the closer, but I’m trying to do my best to help the team win.”

A first-time All-Star last year, Adam is again leading the team in holds (17), although his performance deteriorated in June. He had a 2.25 ERA in eight innings after activation in April, did not allow a run in 12 innings in May and then saw his ERA balloon to 5.11 while allowing four homers in 12⅓ innings last month.

Adam last appeared in a game on Monday when he allowed a run in the eighth inning of a 3-2 loss at Wrigley Field. He was expected to undergo imaging on Thursday.

“It wasn’t something that was super bothering him,” Padres manager Craig Stammen said of Adam’s shoulder strain. “Really had nothing going on shoulder wise until just (Wednesday).”

Added Stammen: “Throwing program didn’t go so well. Right shoulder strain — just felt like he couldn’t get it going. Felt like the safest thing was to put him on the IL, call German up. So hopefully Jason’s injury isn’t too long, and that we just give him a little breather, and then he can be back helping our bullpen again.”

‘Ready to do anything’

Márquez had a 5.76 ERA in 29⅔ innings to begin the year in the Padres’ rotation. He landed on the injured list on May 3 with inflammation in his forearm nerve, began a rehab assignment with Triple-A El Paso on June 2 and had allowed three earned runs in 15⅓ innings when the Padres asked him to work out of the bullpen with El Paso.

Márquez made his MLB debut in September 2016 as a reliever, making three appearances before closing that year with three starts. He’d essentially be a starter ever since.

“It’s still the same baseball,” Márquez said. “I have to be ready for one inning or five innings. I’ve been throwing a lot of games, but I’ll be ready for one inning or five innings.”

Márquez allowed two runs in 1⅔ innings after entering a game in the middle of an inning on June 23. On Tuesday, he allowed three runs in two-thirds of an inning.

Márquez will initially work out of the bullpen. Depending on how things unfold as the Padres navigate the rest of these 17 straight games to close the first half, he could also grab a start at some point.

The inflammation in his forearm is well behind him, he said.

“It feels good,” Márquez said. “I was over there grinding and I feel good. Ready to do anything I can to help the team.”

Notable

C Luis Campusano (toe, oblique) homered in his first rehab game on Tuesday while playing catching six innings for Triple-A El Paso. He was off Wednesday and back in El Paso’s lineup on Thursday. His return to the Padres will hinge on getting back to catching a full nine innings, playing back-to- back days and being able to handle catching four out of five games, Stammen said.