The Yankees reached Lackey (8-10) for six hits and three walks but turned them into just one run. The right-hander struck out one Yankee while registering his first win since July 12 -- a span of a six starts.
Ellsbury finished 3-for-5, including an RBI single that gave Boston a 3-0 lead in the fourth inning and a run-scoring double in the sixth for a 5-1 Red Sox advantage.
David Ortiz (2-for-4, two runs scored) cracked a solo homer for the American League East-leading Bosox, who snapped a three-game losing streak.
Yankees starter Hiroki Kuroda (11-8) coughed up five runs (three earned) on 11 hits in a 5 2/3-inning effort.