SEATTLE -- Less than 24 hours after celebrating their improbable postseason berth with a messy champagne celebration, the A's didn't let up when they returned to the field, striking for eight runs.
Yet they also left 10 on base, and a two-out error by third baseman Matt Chapman in the ninth inning set up Kyle Seager's game-tying single against A's closer Blake Treinen. The Mariners later walked off under the watch of righty Emilio Pagan, who surrendered a two-run homer to pinch-hitter Chris Herrmann in the 11th inning of a 10-8 loss -- Oakland's first this year when leading after seven innings.
They were 68-0 in previous attempts.
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"I don't know how many times that's happened, and not in any seasons that I've managed, so it happened once," A's manager Bob Melvin said. "Certainly a pretty good track record up until this point."

The loss significantly lessened the A's chances of hosting the American League Wild Card Game; with four to play, they trail the Yankees by 2 1/2 games for the top spot, which comes with the perk of home-field advantage. Oakland's loss also helped the Astros clinch the AL West title.
The A's would prefer to treat their own fans to a playoff game -- the Coliseum hasn't seen one since 2013 -- rather than tackle the winner-take-all tilt within the confines of Yankee Stadium. Yet playing on the road doesn't startle them; the A's have thrived away from home this season, going 45-32.
The A's day-after lineup featured two fewer regulars, yet they managed just fine without Khris Davis and Stephen Piscotty, compiling 16 hits -- including three from leadoff man Nick Martini, and two apiece from Matt Chapman, Jed Lowrie, Matt Olson and Matt Joyce, who made good on his first start since July 3. Shortstop Marcus Semien, who repeatedly refuses rest, collected his 14th homer of the season, giving the A's a Major League-leading 128 on the road.

Lefty Brett Anderson had a less-than-stellar outing, though, allowing five runs on seven hits -- including homers to Nelson Cruz and Jean Segura -- in 2 1/3 innings to barely outlast Mariners starter Mike Leake, who was knocked around for six runs in 1 1/3 innings.
Melvin, who would prefer to rest his relief arms leading into October, instead was forced to use seven of them. He said postgame that Lou Trivino (sore neck) and Cory Gearrin (triceps) were unavailable.
"Today was just one of those days where I felt like it took perfect pitches to get them out and everything in play either found a hole or was hit hard," Anderson said. "If I do any semblance of my job, we should've won this game. Unfortunately that wasn't the case."
MOMENTS THAT MATTERED
The A's bullpen staved off the Mariners for much of the way, before Fernando Rodney surrendered two runs to his former team to make it a one-run game after eight. Treinen recorded two quick outs, but Cruz tagged him for a single, and Ryon Healy joined him on the bases when Chapman bobbled a ground ball, leading to Seager's game-changing hit.
Treinen was consequently hit with his fifth blown save and first since July 21.
"Just bobbled it," Melvin said. "That's not what lost the game for us. We left 10 on base, had some opportunities to score a bit more. It never comes down to one play. As good as he's been, we need to pick him up, too."

HE SAID IT
"Maybe I should've partied a little bit harder last night. I did the responsible thing and went home and got a good night's sleep and wasn't hungover today. And maybe I should've gone a little harder and had better results." -- Anderson, on the A's clinching celebration
UP NEXT
Right-hander Edwin Jackson, a candidate to start next week's Wild Card Game, will toe the rubber for Wednesday's 7:10 p.m. PT series finale in Seattle. The Mariners will counter with right-hander Felix Hernandez (8-13, 5.46). Jackson held the Mariners to one run over six innings on Sept. 2.