Detroit starter Justin Verlander earned the win in his first July start, something he couldn't do in five June outings. The right-hander went 0-3 with a 6.82 ERA over five starts in June, but quickly made amends on Wednesday.
Verlander (7-7) went six innings and allowed just two runs on nine hits with four strikeouts. He didn't allow a walk for the first time all season.
Brandon Moss went 4-for-4 and came a triple shy of the cycle, knocking in two runs for the A's, who concluded an eight-game road trip with three straight losses following four straight wins.
Coco Crisp also homered in the setback.
Jesse Chavez (6-5) was touched up for five runs on eight hits and four walks over five-plus innings.