Working through some struggles, the A’s offense may have found some momentum in Seattle.

Held to one hit through the first seven innings of Friday’s 5-3 loss to the Mariners, the A’s bats showed life with a three-run eighth inning, which broke a rough stretch that had seen the A’s held to four runs through their previous 29 innings.

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The late rally was highlighted by a two-run triple by Marcus Semien, who later would score on a sacrifice fly by Ramón Laureano. All three runs came off Mariners reliever Bryan Shaw, which erased the frustrations built up by A’s hitters against starter Taijuan Walker, whose only blemish through seven frames was a double by Laureano in the fourth. Mark Canha drew a leadoff walk in the ninth, but Taylor Williams was able to shut the door on the A’s.

A’s manager Bob Melvin isn’t ready to sound the alarm seven games into the regular season, though he did admit concern after examining the team’s offensive numbers to begin the season. Following Friday’s defeat -- Oakland’s third in a row -- the A’s now rank last in the American League in team OPS (.589) and have the second-lowest team batting average (.194).

“I was looking at our offensive numbers today and they weren’t great as far as the league goes,” Melvin said. “We didn’t have a good offensive game again today, and when you’re not hitting on all cylinders, you end up getting beat with the intrinsic stuff. We’re gonna have to swing the bats better.”

The clutch hit also continues to elude the A’s, who are now 1-for-21 with runners in scoring position over their three-game losing streak.

“It certainly is not a 162-game season where you just don’t worry about things until you’re 80-100 games in. The season is going to be over,” Melvin said. “It’s that way for every team. We got off to a good start winning three out of four, and the last three games we just haven’t played well.”

The offensive woes seem to be carrying over in the field. Ranked among the top defensive clubs in 2019, the A’s committed two costly errors on Friday, bringing their total to five through their first seven games.

“Once we got into the bullpen, our at-bats got better, which they tend to do for us later in the game,” Melvin said. “We just put ourselves in too much of a hole to begin with.”

The first error came in the fourth from 2018 and ‘19 Gold and Platinum Glove Award winner Matt Chapman, who after charging in on a chopper by Austin Nola made an off-target throw to Matt Olson at first base on a potential inning-ending play that instead led to Seattle’s third run of the frame.

The next error came from reliever J.B. Wendelken, who entered the game in the fifth in relief of starter Sean Manaea and missed wide on a throw to second base following a comebacker. Had the throw been on target, the A’s would have had an inning-ending double play to keep the deficit at three. Instead, Seattle kept a rally going and later scored two runs to push its lead to 5-0.

“I think you’re seeing it a little bit around the league,” Melvin said of the defensive miscues. “That was the thing that stood out to me when we came back for Summer Camp. It was taking guys a while to get there defensively. We just haven’t been like we usually are. We don’t usually give runs away like we did today, and it ended up costing us.”

Manaea had some encouraging moments in his start, including an uptick on his fastball velocity to around 92 mph, but he ran into trouble his second time through Seattle’s order. After Manaea retired his first nine batters, the Mariners figured something out in the fourth, tagging the left-hander for three runs.

The outing was a near copy of Manaea’s first start of the season last Saturday against the Angels, in which he retired 12 of his first 13 batters before being relieved in the fifth with four runs allowed.

With a shortened ramp up to the regular season leaving pitchers with less time to build their workload, Melvin said that Manaea’s troubles facing the Mariners a second time through the order may have been due to the lefty's lack of stamina.

“They hit some balls the other way on him, but I don’t know that it was a different approach,” Melvin said. “I think it’s just that he’s still getting his endurance. Hopefully, instead of three good innings, we’ll get five or six next time out.”

Manaea said his “pretty bad outing” was not a result of arm fatigue. It just came down to straying away from his ability to execute his pitches after the first three innings. The end result: He took his second loss of the season, charged with five runs (three earned) on six hits over 4 1/3 innings.

“It was good for the first two or three innings and just fell off. I don’t know how to explain that,” Manaea said. “I don’t really know what to pinpoint. I think it’s just coming down to me executing pitches. I just haven’t been doing that. I think the arm strength is there. It’s just me executing pitches.”