Lester (14-8) yielded just three hits and two walks while striking out five in the 115-pitch effort, notching his fourth victory in six starts.
Shane Victorino, David Ortiz, Jonny Gomes and Daniel Nava and Will Middlebrooks each supplied an RBI for the American League East-leading Red Sox, who clinched their three-game series against the Yanks.
CC Sabathia (13-13) was reached for five runs in nine hits over six full innings for New York, which came into the contest two games out of an AL wild card spot.
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