The A's overcame an early four-run deficit brought about when Shelley Duncan hit a grand slam homer in the fourth. Oakland got three of those runs back in the bottom half of the inning, with Donaldson's double driving home one of them.
A sacrifice fly in the fifth by Chris Carter created a 4-4 tie.
The eighth-inning runs made a winner out of Jordan Norberto (4-1), who recorded the final two outs in the seventh and retired the side in the eighth.
Grant Balfour struck out one in a perfect ninth for his 10th save.
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