HOUSTON -- The A's entered their weekend series against the defending world champion Astros without a key bullpen contributor. Lefty Ryan Buchter was lost to the disabled list with a left shoulder strain and will be shut down from throwing for upwards of two weeks.
Thursday's move was accompanied by several others: Right-hander Yusmeiro Petit was reinstated from the bereavement list, and lefty Danny Coulombe was recalled from Triple-A Nashville. In addition, trade acquisitionWilmer Font joined the A's bullpen.
Buchter had a 1.69 ERA in 13 relief appearances and was riding a six-game scoreless streak after allowing four runs over his first seven games. He struck out his only batter in Wednesday's game in Arlington before departing with shoulder discomfort.
"[Buchter's] been kind of going back and forth with it," A's manager Bob Melvin said. "Some days it felt good, some days it didn't feel as good. Once we saw the velo the other day, we knew that was probably his worst day, as far as how he's feeling.
"He's been really good for us, and it's tough to do without your late-game lefty, but we're going to have to do without him for a period of time."
Coulombe, who pitched to a 5.79 ERA in nine relief appearances before being optioned to Triple-A, won't necessarily be called upon in situations typically reserved for Buchter. Petit, rather, will likely be Melvin's go-to guy in these spots.
"We'll feel it out and see how it goes," he said.
Font, meanwhile, will be reserved for long-relief duties. He was 0-2 with an 11.32 ERA and .383 opponents batting in six relief appearances with the Dodgers before he was designated for assignment Monday. Los Angeles traded him to the A's for Minor League left-hander Logan Salow on Wednesday.
A's move on without Graveman
After demoting Opening Day starter Kendall Graveman on Thursday's off-day, Melvin explained the team's reasoning on Friday.
"That was a hard one," Melvin said. "There are certain moves that are a little bit more impactful with your team than others. Kendall is a leader for us. I talked to the group a little bit here before we came out here about the situation, and really the thought and the thinking within the organization is he just needs to go down and refine what he's doing and relax a little bit.
"I think he was trying awfully hard. As a guy that starts Opening Day for you, you go through a drought where you haven't won games, now each and every time you go out there, there's more pressure for you to perform. Couple that with he's changing his repertoire a little bit, he's making some mechanical adjustments, so hopefully he can do this without pressure, hopefully it's just a couple of starts because we're going to need him and I know these guys are going to miss him too."
Graveman was 0-5 with an 8.89 ERA in six starts, leading the Majors in losses, runs (28) and hits (41). The A's could utilize a fifth starter Wednesday if they choose, but could do without one until May 4. Left-hander Brett Anderson is the leading candidate.