After being shut out for six innings by Ian Kennedy (3-5), the Tigers finally broke through with three runs in the seventh frame. After Miguel Cabrera led off with a single, Boesch homered to right to put Detroit up 2-1.
Guillen then followed with a solo blast, helping the Tigers take the rubber match of a three-game set with the D-backs at Tiger Stadium.
Max Scherzer (4-6) pitched seven solid innings, allowing only one run on four hits over seven innings, striking out eight and walking two. Jose Valverde got his 16th save with a scoreless ninth.
Kennedy pitched well in defeat, surrendering six hits, walking none and fanning five.