Mitch Moreland's pinch-hit three-run homer with one out in the top of the ninth gave the Red Sox their first victory of the season.
Rafael Devers doubled off Hunter Strictland to start the inning, with the Mariners holding a 6-4 lead. A passed ball put Devers on third and Blake Swihart (batting for Sam Travis) was hit by a pitch. Jackie Bradley grounded to first and Devers was tagged out at the plate. Moreland, who had started loosening up for a possible late-inning at-bat in the middle innings, hit for Christian Vazquez and crushed Strictland's 2-0 pitch. Its exit velocity of 114 mph was the third-hardest home run by a Boston player since 2015.