Brandon Lyon (2-2) earned the victory after inducing Boston's Dustin Pedroia to ground out to end an eighth-inning threat.
Clay Buchholz (11-6) absorbed the loss, giving up four runs on seven hits and three walks over 8 2/3 innings.
Pedroia and Jacoby Ellsbury each hit homered for the Red Sox, who fell for the 11th time in 12 games.
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