Terms of the deal weren't revealed but CBS Sports reported the 36-year-old will receive $15.5 million, including a vesting option for 2016.
Benoit converted 24-of-26 save opportunities for the Tigers last season, posting a 2.01 ERA over 66 appearances.
Since 2010, the right-hander has gone 14-9 with 29 saves and a 2.53 ERA -- fourth-best in baseball for pitchers with at least 250 innings pitched during the span.
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