OAKLAND -- It's no secret that Jesse Winker has scuffled this season. He was one of Seattle's splashiest offseason pickups, but his paltry .219/.337/.335 slash line hasn't lived up to expectations.

Winker's struggles at the plate persisted for so long that he was held out of the lineup on June 14. But perhaps that day off was just what he needed to regroup and hone his approach. In the week since, Winker has slowly but surely started to look more like himself -- and his bat was key in Wednesday's series-clinching 9-0 win over the A's at the Coliseum.

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No one likes to be benched, but the day off allowed Winker to slow down and continue making adjustments in his first season in Seattle.

"It's a new division for me, it's a new side of the country and it was just a chance to take a breather and take in a baseball game," Winker said. "It was good for me."

In eight games since, Winker has gone 7-for-21 with three extra-base hits and seven walks, with much of his increased production coming in this series in Oakland.

On Wednesday, Winker went 2-for-4 and knocked in three runs for the Mariners, matching his season high. He brought home Julio Rodríguez with a liner to right field in the third inning, then he scorched an offering from Oakland starter Paul Blackburn deep to center for a two-run shot in the fifth.

Winker was one of four Mariners to record multiple hits against the A's on Wednesday, giving him back-to-back multi-hit games for just the third time this season. He went 2-for-4 with a double and a home run in Tuesday's series opener, showcasing the power that has been eluding him this season.

Winker is coming off an All-Star season with Cincinnati in which he set career highs in the majority of his offensive stats, including doubles (32), home runs (24) and OPS (.949). He ended 2021 with a 140 OPS+, but nearly halfway through 2022, his 94 OPS+ puts him below league average for the first time in his career.

Entering Wednesday, Winker was slugging .319 -- which is down significantly from his career mark of .477. The disparity between his expected slugging percentage (.453) and his current slugging percentage is negative-.134, the 12th-largest differential in the American League. Manager Scott Servais said it's encouraging to see Winker hit for power in this series.

"His confidence is coming back. He's not over-swinging," Servais said. "He feels really good; he's seeing the ball good in this ballpark. He knows if he just squares it up, it'll go, and that's what happened again tonight."

One aspect of Winker's game that has remained consistent is his ability to get on base. He's drawn a walk in each of his last nine starts, and he leads the AL with 44 free passes.

"You always have value if you're getting on base, and Jesse leads the league in walks," Servais said. "He does swing at the right pitches, but eventually you've got to start squaring some balls up.

"It's been a struggle for him to get back to who he is, and it's headed in the right direction right now."

Seattle's offense appears to be picking up steam after a difficult 3-8 homestand in which the team averaged 2.5 runs per game. The Mariners have erupted for 17 runs in the past two games in Oakland, getting contributions from up and down the lineup. All but three players who appeared on Wednesday recorded at least one hit, and every starter reached base at least once.

Back-to-back romps in Oakland have considerably boosted the Mariners' spirits. Rookie starter George Kirby, who tossed six scoreless frames and picked up his second big league win, said he sees that positive energy translating into the team's at-bats.

"We're having a lot of fun," Kirby said. "That counts for a lot of things."

Winker, for one, thinks it's only a matter of time before he and the rest of the team get rolling for good. Servais agrees -- sometimes all it takes is one person to light the fuse, and that's what he sees in his team right now.

"Hitting is contagious," Servais said.