J.A. Happ (3-1) pitched five innings for the victory, allowing one run and four hits with two walks and eight strikeouts.
Nelson Cruz and Seth Smith also each had a pair of hits and an RBI for Seattle, which scored five runs on Oakland’s most errors since Aug. 22, 2012, against Minnesota. The Athletics lead the majors with 32 miscues.
Jesse Hahn (1-3) gave up six runs and eight hits in 5 1-3 innings. He walked three and struck out four.
Mark Canha hit his fifth home run for the A’s in the eighth, and Marcus Semien finished with three hits.
The Cano-Cruz combo produced one run in the first and a rare double-error by shortstop Semien sent home another.
Cruz doubled home Cano, and after Kyle Seager walked, Logan Morrison hit a sharp grounder up the middle but it caromed off Semien’s glove. Semien then threw wildly to home, allowing Cruz to score.
Cruz’s infield single in the fifth triggered a throwing error by third baseman Brett Lawrie that sent two more runs home.
Lloyd McClendon earned his 100th victory as the Mariners manager.
Athletics: It’s so bad for the A’s this season that even their injured players are getting injured. RHP Jarrod Parker, coming back from a second Tommy John elbow surgery, had a setback Friday, grasping his elbow in pain after a pitch for Triple-A Nashville. “You hope for the best but watching the video, it breaks your heart,” manager Bob Melvin said. RHP A.J. Griffin, also coming back from elbow surgery, flew back to the Bay Area to have his ailing right shoulder examined. The extent of either injury has not been determined. … LHP Sean Doolittle (strained rotator cuff) is tentatively scheduled for a rehab assignment Monday and Ben Zobrist (left meniscus tear) is expected to take batting practice Monday.
Mariners: RHP Hisashi Iwakuma (strained lat dorsi muscle) is not expected back with the club until at least the end of the month.
Mariners: RHP Felix Hernandez (5-0, 1.73), the only AL pitcher with five wins, will be shooting for a 6-0 record against the A’s. He also needs five strikeouts for 2,000 in his career. At age 29 and 32 days, he would be the fourth-youngest pitcher in history to reach that milestone.
Athletics: RHP Jesse Chavez (1-2, 1.80) will be making his fourth start after beginning the season in the bullpen. He won his previous outing — 2-1 at Minnesota on Tuesday — his first victory since July 23, 2014. He is 0-2 with a 2.48 ERA in 12 career appearances against Seattle, including three starts.
MILLER TIME IN LEFT
Brad Miller, who started 25 games at shortstop until injured Chris Taylor came off the DL, is transitioning to left field. McClendon, who played five positions in his eight-year career, said the biggest adjustment will be getting enough carry and accuracy on his arm. “When it’s all said and done, I think we’re going to have a guy who can play all (seven) positions,” McClendon said.