Seattle, WA – Josh Reddick crushed a go-ahead, two-run homer 4, in the first of three meetings between the clubs.
David Ortiz went 2-for-5 with a home run and two RBI, and Jed Lowrie also went deep for Boston, which has won five of six overall.
John Lackey (11-8) won his sixth straight decision after giving up four runs on 10 hits in six-plus frames.
Blake Beavan (3-3) was touched for six runs on 11 hits in 6 1/3 innings in defeat, the Mariners' fourth in five games.