Joakim Soria’s revitalized 2020 campaign has elevated him into a key role in the A’s bullpen. That’s why it came as a surprise on Monday when the veteran right-hander suddenly was unable to throw strikes.

Summoned by A’s manager Bob Melvin in the sixth with the task of protecting a one-run lead, Soria faltered in a 6-5 loss to the Mariners in the first game of a seven-inning doubleheader at T-Mobile Park. Beginning the sixth with a strikeout, Soria did not finish the frame after allowing a double and three straight walks -- including one with the bases loaded that brought home the go-ahead run for Seattle.

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Entering the day, Soria had issued more than one walk just twice in 18 appearances. On Monday, the righty was tagged for two runs on two hits and three walks, recording just two outs in the sixth.

“He’s been so reliable for us,” Melvin said. “He’s pitched with traffic and gotten out of jams. This time he didn’t do it. This is a tough one for us. This is a game we usually win.”

An appearance by the A’s bullpen seemed unlikely the way Jesús Luzardo was going. Provided a 5-0 lead entering the bottom of the fourth, Luzardo cruised until the fifth, when he surrendered two home runs and departed with just two outs as Oakland’s lead shrank to one run. He finished with four runs allowed on seven hits, striking out seven over 4 2/3 innings. All four runs came on a trio of homers.

“His stuff was great the whole game, just at times he tries to overthrow and that’s when he misses location,” Melvin said. “He gave up a couple of unexpected homers there, next thing you know he comes out of the game.”

Though Luzardo was superb in his previous start last week against the Astros, his struggles in the fifth on Monday evoked flashbacks to his outing against the Padres on Sept. 4, when he also was strong for four innings before finding himself in a jam he was unable to escape in the fifth.

The common issue from that Padres start and Monday’s outing comes in Luzardo’s third time facing the batting order. After seeing opposing hitters only twice during starts in the Minor Leagues, the rookie is now getting a bigger workload as he pitches deeper into games. Luzardo understands why the issue keeps arising and knows only he can fix it.

“I think I probably didn’t change it up third time through the order,” Luzardo said. “Same thing that happened with San Diego. This is my first year facing hitters a third time through the lineup and I need to make adjustments. I didn’t make them today.”

One way Luzardo said he planned to combat the problem after the start against the Padres was to attack hitters and get ahead in counts early. He did that Monday through four innings, throwing first-pitch strikes to nine of the first 16 batters he faced. But the fifth inning was a different story.

“It’s not good, especially losing a game like this. I take it pretty personal,” Luzardo said. “They gave me a five-run lead, and I go out in the fifth and give up a four-spot. It’s not what anyone wants, especially in a doubleheader. You want to go as deep as you can and keep your team in the game. That fifth inning was not good and losing this game was tough.”

On a day where smoke was clearly visible in the air at T-Mobile Park as Mariners officials monitored the poor air quality caused by wildfires throughout the region, Luzardo did not use the conditions on the field as an excuse. Though he clearly felt a difference in the air quality on the mound.

“When I came out I think [the air quality index] was at 284,” Luzardo said. “I’m a healthy 22-year-old. I shouldn’t be gasping for air or missing oxygen when I’m getting to the line. I’ll leave it at that.”