Infante's three-run blast in the second put the Tigers ahead to stay and his two-run shot made it 6-2.
After the Indians narrowed the deficit to 6-5, Austin Jackson's two-run triple in the eighth put the game out of reach.
Anibal Sanchez (12-7) allowed three runs on six hits through 6 2/3 innings for American League Central-leading Detroit, which opened up an 8 1/2-game advantage over second-place Cleveland.
Indians starter Scott Kazmir (7-7) was tagged for four runs on seven hits in a five-inning effort.
Carlos Santana lofted a two-run homer, finishing with three RBI, and Yan Gomes added a solo shot for the Tribe.