Boston (79-34) has won eight of nine games and owns the majors’ best record.
The Yankees hadn’t been swept in a four-game series by the Red Sox when they entered a series 30 or more games over .500 since 1939, according to the Elias Sports Bureau.
Sandy Leon looped a two-out single off Jonathan Holder (1-3) in the 10th and advanced on a wild pitch. Tony Renda pinch-ran before Benintendi’s single bounced up the middle to the right of second-base.
Matt Barnes (4-3) worked a perfect inning in the top of the 10th.