It came one night after Ross hit three-run homers in consecutive innings of a 10-1 win.
Boston took three of four games in the series and is 5-2 since the All-Star break.
It was the fifth loss in 13 games for AL Central-leading Chicago, which opens a three-game series at second-place Detroit on Friday night.
Ross cranks 3-run homer to lift Red Sox in 9th
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