"About a month ago, I took a swing and felt a pop," Lowrie said. "I've just been trying to manage it ever since then. I was hoping the symptoms would get better, and they just haven't."
Lowrie is hitting .263, but just .177 over his last 15 games. The A's will use Max Muncy and Tyler Ladendorf at second base for the foreseeable future.
"We were hoping it would get better with some time off," A's manager Bob Melvin said. "He was trying to tape it differently and so forth to alleviate some of the discomfort. That hasn't been the case. We appreciate the fact he's going out there and playing hurt, but it's gotten to the point where he has to go on the DL."
Hahn, meanwhile, lands on the DL with a strained right shoulder. The 27-year-old had just rejoined the A's rotation this week after the club dealt Rich Hill to the Dodgers before Monday's non-waiver Trade Deadline. Hahn lasted four innings in his start against the Angels on Thursday, surrendering five runs on 87 total pitches.
Melvin said the team noticed Hahn's velocity drop in the fourth inning of Thursday's start, prompting his removal. Hahn doesn't believe the injury is serious, saying he hopes he'll return in 15 days -- a timeline Melvin said was "optimistic."
"I don't really feel any discomfort," Hahn said. "I've dealt with injury before. I know what injury feels like. This doesn't feel like anything I can't get through. It just honestly feels like August pains; it's that time of the season."
Melvin was asked whether rookie Daniel Mengden is a candidate rejoin the rotation and replace Hahn. Mengden was sent down July 26 after showing signs of fatigue, and Melvin didn't commit to a quick return for the righty.
"Maybe to rush him back here might not be the thing to do," he said. "We might go a different direction. We haven't really made up our mind yet."
Eibner, who was acquired from the Royals on July 30 in exchange for Billy Burns, was 4-for-13 (.308) with two doubles, a home run and two RBIs in four games with Nashville. Eibner made his Major League debut with Kansas City earlier this year, hitting .231 with six doubles and three homers in 26 big league games.
This will be Triggs' eighth stint with the A's this season. He owns a 5.40 ERA through 17 big league appearances in 2016.