SEATTLE -- Brett Harris feels right at home in the Pacific Northwest.

Soon after high school, Harris entrenched himself with the state of Washington, where he continues to reside for part of the offseason when he’s not back in his hometown of Chicago. Following two years at the University of Houston and Central Arizona College, he transferred to Gonzaga University in 2019. It’s where he met his fiancée, Sydney, whose entire family drove up to Seattle for the entirety of this weekend’s three-game series between the A’s and Mariners at T-Mobile Park.

While attending Gonzaga, Harris made the four-hour road trip from Spokane to Seattle several times to catch Mariners games, even as recently as 2021 just before he was drafted by the A’s later that summer.

Three years later, Oakland’s No. 9 prospect was reacquainted with that same ballpark as the site of his first three road games as a big leaguer.

“It’s a full-circle moment,” Harris said. “It looks a lot different when you’re on the field instead of watching from the stands. It’s really cool to go from just a fan here a few years ago and now be playing here.”

After shining with his defense in Saturday’s win, Harris would have preferred a better outcome in the series finale. He was one of several A’s hitters who struggled to get much going against Luis Castillo in Sunday’s 8-4 loss to the Mariners.

Alex Wood dug the A’s an early hole. He was pulled after just two innings in which Seattle plated five runs and generated a ton of hard contact. Six of Seattle’s 10 balls hit in play against him registered an exit velocity of 100.2 mph or higher, including Julio Rodríguez’s two-run blast in the second that was tagged 109 mph off the bat to give the Mariners a 5-0 lead.

After the game, manager Mark Kotsay revealed that Wood has been dealing with a shoulder issue for some time now, which appeared to worsen on Sunday. The left-hander’s sinker averaged 88.6 mph, over 2 mph slower than his season average.

“Alex has been grinding,” Kotsay said. “He hasn’t felt great. He’s been able to make every start. But today you saw a little drop in velo and his slider wasn’t as sharp. He gave us everything he had for two innings.”

The A’s are already down one rotation member with Joe Boyle sidelined with a lower back strain. Kotsay mentioned the club will likely send Wood for further evaluations on his shoulder, while Wood was unsure if he could make his next scheduled start, during Oakland’s three-game series in Kansas City next weekend.

“We’ll see how the next few days go,” said Wood, who holds a 5.26 ERA through nine starts this season. “I’ve been throwing with it for a little bit now. I’m going to get treatment, manage the workload and go from there.”

Should Wood -- Oakland’s Opening Day starter -- have to miss time, the A’s would likely turn to an in-house option with either Kyle Muller or Mitch Spence, both of whom are currently providing long relief out of the bullpen.

After a season-high six-game winning streak, the A’s have now dropped six of their past eight. Though they’ve enjoyed a surprisingly solid start that saw them enter the day sitting in third place in the American League West with a record of 19-22, Sunday marked Oakland’s second consecutive series loss to a club ahead of them in the division standings, having also lost three of four to the Rangers at home earlier this week.

One positive the A’s will carry into their four-game series against another division opponent in the Astros, which begins Monday night in Houston, is a red-hot Brent Rooker.

Coming off an AL Player of the Week Award, Rooker is making a strong early case for Player of the Month. The 2023 All-Star crushed an eighth-inning two-run blast off Cody Bolton that sailed over the Edgar’s Cantina sign in left field a StatCast-projected 411 feet, at an exit velocity of 113.4 mph, marking the hardest-hit ball of his career. The homer was his 10th of the year and part of a two-hit day. He also crushed a 112.4 mph lineout against Castillo.

In 10 games in May, Rooker is now 17-for-38 (.447) with five homers and leads the Majors with 14 RBIs.

“This is the maturation of Brent,” Kotsay said. “It’s a follow-up of last year and the success he had. The at-bats he had off Castillo were great. He’s seeing the ball really well and taking a great swing.”