Chapman error opens window for Mariners to rally in 9th, win in 11th

Healy reaches on Chapman's error 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 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, and the Mariners 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.

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The loss significantly lessened the A's chances of…