Arizona enjoyed a 15-hit attack that included Stephen Drew's two-run home run in a three-run fifth.
Dan Haren (7-4) coasted to the win by allowing just four hits and a run with eight strikeouts in seven innings. Haren spent three seasons with Oakland and was the starting pitcher for the American League in last year's All-Star Game before being traded to the Diamondbacks for six prospects.
Joe Blanton (3-10) was roughed up for eight runs in three innings.
Arizona, which maintained a 4 1/2-game lead over Los Angeles at the top of the National League West, halted a three-game losing streak.
The Diamondbacks wasted no time getting to Blanton in the first. Drew opened the inning with a single, Conor Jackson had a base hit and Orlando Hudson loaded the bases by reaching on an infield single.
Chad Tracy followed with a two-run double and, after Mark Reynolds struck out and Miguel Montero lined out to shortstop, Young homered to left-center.