OAKLAND -- Luis Perdomo earned his way back into the Padres' rotation with an impressive of couple months at Triple-A El Paso. He may have earned his right to stay in the rotation on Wednesday afternoon.
In a 4-2 loss to Oakland, Perdomo -- making his first big league appearance since April 18 -- put forth his best start of the season. He worked 5 2/3 innings and allowed two runs on four hits, while recording nine outs via the ground ball.
"For the first time back, we're pleased with that," said Padres manager Andy Green. "There's definitely stuff to grow with. We're glad to have him back. … I have every expectation he takes the ball again in five days."
In a tense ballgame, the A's finally broke through against the San Diego bullpen in the eighth. Stephen Piscotty's two-run double off Craig Stammen plated the go-ahead runs, and closer Blake Treinen slammed the door. San Diego got the entirety of its offense on a two-run shot from Christian Villanueva in the second.
As for Perdomo, he was still plagued by a handful of the same issues that forced him to the Minor Leagues. He walked four, and he found himself with too many baserunners. The difference Wednesday: he made quality pitches when he had to, and he managed to escape those jams.

"When guys got on with those walks, I was able to bear down, get some ground balls, get some double plays," Perdomo said.
"They scored in two different innings, one run in each," Green said. "What his issue has been for us in the past is that a one-run inning turns into a five-run inning. ... He had to battle back in both of those innings."
Perdomo was demoted in late April, having posted an 8.36 ERA across his first four starts. But he was excellent in 11 outings for El Paso, earning a callup Wednesday in place of the injured Jordan Lyles.
Upon his return, Perdomo showcased some subtle differences in his pitch mix. He threw as many four-seam fastballs as two-seam fastballs. In the past, Perdomo had relied heavily on his two-seamer to induce ground balls. But on Wednesday, his changeup did the trick. He recorded five of his groundouts and allowed no hits with the pitch.
"It was something I was working on," Perdomo said of his changeup. "I went down there [and] put a lot of focus on that pitch -- all my pitches, really, but the changeup was something I was really focused on."
The Padres insist there's a place for Perdomo in their future rotation plans. But he has yet to build on his solid rookie campaign in 2016. He was solid on Wednesday, but the slumping San Diego offense did him no favors. The Padres have now dropped six straight series and are 4-14 in that stretch.
MOMENTS THAT MATTERED
Renfroe robbed:William Myers drew a one-out walk in the sixth, and Hunter Renfroe followed by hitting a 105-mph laser down the third-base line. If not for Matt Chapman, it probably would've scored Myers. At the very least, the Padres would've had two men in scoring position for Villanueva. But Chapman made a fantastic sliding stop, and he sprung to his feet to start an inning-ending double play.

Left stranded: San Diego's best chance at a late lead came in the eighth when Freddy Galvis led off with a double. With a tough left-on-left matchup against former Padres pitcher Ryan Buchter, Green called for a Travis Jankowski bunt. Jankowski popped it up. Galvis likely would've scored from third on Manuel Margot's ensuing flyout to center. Instead, after Eric Hosmer and Myers walked, Galvis was stranded when Renfroe flied out.
'ALL AROUND, ONE OF THE BEST GAMES HE'S PLAYED'
For the most part, the Padres' offensive struggles continued on Wednesday. Villanueva's did not. He went 2-for-4, and his second-inning blast brought his team-leading home run total to 17. It was his first homer in July -- matching his total for the entirety of June.
Perhaps as notable: Villanueva was tested defensively with the ground-ball-heavy Perdomo on the mound. He made every play. The rookie third baseman has shown remarkable growth from his early-season struggles at the hot corner. His best play came in the fourth when he ranged to his right and picked a short-hop with his backhand, before throwing perfectly on the run to nail Piscotty.
"All around, one of the best games he's played," Green said. "From start to finish, he was outstanding."

YOU GOTTA SEE THIS
Galvis has a tendency to make very difficult plays look very easy at shortstop. With one out and a man on third in the second inning, the Padres brought the infield in against Chapman, who sent a high pop into shallow left. At normal depth, it would've been an easy play for Galvis. But he was on the infield grass when Chapman made contact. Galvis retreated backward and made a brilliant over-the-shoulder basket catch, holding the tying run at third.

HE SAID IT
"Guys are grinding. Guys are going out and giving everything they've got every single day, and that frustration carries over into the box sometimes, because they haven't come through very often lately. Guys feel that. Sometimes the best thing you can do is relax and go play baseball. Enjoy what you're doing, and the hits will start coming." -- Green
UP NEXT
The Padres head to Arizona, where they'll open a four-game series against the division-leading D-backs on Thursday at 6:40 p.m. PT. Left-hander Eric Lauer gets the ball after an excellent June in which he posted a 2.76 ERA and lowered his overall mark from 7.67 to 5.08. He's seen an uptick in his fastball velocity, while adding some bite to his slider. Arizona counters with right-hander Shelby Miller.