With the game tied 4-4 in the eighth, the Tigers began a three-run outburst when Avisail Garcia's lead-off fly ball to right appeared to have been caught by Boston's Daniel Nava, who when dropped it on the transfer to his hand.
But second base umpire Mike DiMuro ruled Garcia safe, prompting a vociferous argument from Bosox Manager John Farrell, who was thrown out of the game.
Hunter followed with a sacrifice fly, sending home the go-ahead run, and after Miguel Cabrera was intentionally walked, Craig Breslow entered the game and surrendered a two-run single to Prince Fielder (three RBI).
Joaquin Benoit (2-0) earned the decision despite allowing a run in the ninth as the American League Central-leading Tigers took three-of-four games from AL East leaders Boston.
Wisconsin business offering 'therapeutic cuddling' forced to close
Costly malfunction causes beer flood at Boston-area brewery