Robbie Ross (4-2) walked Michael Saunders with two away before giving up the homer to right by Seager. He had three of Seattle's 10 hits.
The win went to Charlie Furbush (2-4), who did not give up a hit in 1 2/3 innings of relief. Tom Wilhelmsen worked a perfect bottom of the 10th for his 17th save.
Seattle starter Felix Hernandez gave up two runs on seven hits with seven strikeouts, but suffered his third consecutive no-decision.
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