SEATTLE -- Oakland A's starting pitcher Jarrod Parker wasn't exactly looking ready for the postseason Saturday afternoon, when his team was fortunately just playing out the string.
Parker gave up three home runs -- two of them to Seattle's Brad Miller, including a fifth-inning grand slam -- and matched his shortest outing since April in a 7-5 loss to the Mariners.
Parker (12-8) lasted just 4 1/3 innings, having allowed seven earned runs off seven hits before exiting the game with the A's trailing 7-1. The performance came 12 days after the Los Angeles Angels tagged him for eight hits and seven earned runs over 4 1/3 innings of a 12-1 loss in Oakland.
Miller did most of the damage while recording his third multi-homer game of the season. He hit a solo shot in the third inning to give Seattle a 3-1 lead, then took Parker deep for a fifth-inning grand slam.
Miller has now hit eight home runs on the season, and all but two of them came in his three multi-homer games.
Justin Smoak also went deep on Parker with a two-run shot in the second inning, giving the Mariners (71-90) a 2-0 lead.
Seattle starter Brandon Maurer (5-8) turned in his second consecutive solid start, allowing two runs and six hits over 5 1/3 innings to earn his first win since Aug. 20.
The A's rallied against the Seattle bullpen, scoring three runs on a pair of two-out, back-to-back homers in the seventh inning, but it wasn't enough. Oakland failed to capitalize on a bases-loaded situation in the eighth, when Jed Lowrie struck out looking to end the inning.
The Mariners' Danny Farquhar came on to pitch a scoreless ninth inning to earn his 16th save of the season.
Oakland (95-66) has now lost three of its past four but had very little on the line Saturday. The A's already clinched the AL West as well as homefield advantage for the AL Division Series that begins Friday, and they had already been mathematically eliminated from catching Boston in the race for the AL's best record.
The Mariners jumped on Parker for three runs in the first three innings, thanks to a pair of home runs. Smoak took Parker deep for a two-run homer in the second inning, then after the A's got one run back in the top of the third, Miller went deep for a solo shot that put the Mariners ahead 3-1.
Miller's home run could have been a two-run shot if not for a base-running gaffe from teammate Nick Franklin in front of him. Franklin hit a leadoff triple into the right field corner but was thrown out trying to stretch it into a triple. Miller then took Parker deep on the next pitch.
Miller added a grand slam in the fifth inning on his way to a 2-for-4 performance with five RBIs.
Oakland's Brandon Moss and Alberto Callaspo hit back-to-back homers off Mariners reliever Chance Ruffin in the seventh inning. Moss hit a two-run shot to right field, then Callaspo followed with a solo homer to cut Seattle's lead to 7-5.
Farquhar struck out both Moss and Callaspo during a 1-2-3 ninth inning to earn his 16th save in 18 chances since replacing Tom Wilhelmsen as the Mariners' closer in early August.
NOTES: Before Saturday's game, Mariners manager Eric Wedge tried to clear up some details on his decision not to come back next season. After reading reports that his decision to turn down a one-year extension was at the heart of his announcement, Wedge said Saturday that the rift with the team goes deeper than that. "If they'd offered me a five-year contract," he said Saturday, "I wouldn't be back here." Wedge offered that his philosophies and those of front-office types like general manager Jack Zduriencik, team president Chuck Armstrong and CEO Howard Lincoln have drifted apart over the years. "You have to have consistency with personnel," Wedge said. "Every time you turn over (the roster), you start over to a certain extent." ... A's OF Yoenis Cespedes (shoulder) was feeling a "little bit better," on Saturday, manager Bob Melvin said, but he was held out of the lineup after feeling discomfort in his shoulder Friday night. Cespedes came out of Friday's game in the fourth inning, and it appears he probably won't play again this weekend. With Oakland's first postseason action still six days away, Cespedes should have plenty of time to get healthy for the playoffs. ... Smoak's second-inning home run was his 20th of the season, giving him a new career high. ... Oakland's Moss now has three home runs in his past four games played, including two in the first two games of the Seattle series.