The 30-year-old Willis spent parts of nine seasons with the Marlins, Tigers, Diamondbacks and Reds. Over that span, he compiled a major-league record of 72-69 with an ERA of 4.17.
Originally an eighth-round choice of the Cubs, Willis was dealt as a minor-leaguer to the Marlins in 2002.
As a rookie, Willis was a key member of the Marlins' team that won the 2003 World Series. In that World Series, Willis logged 3.2 scoreless innings of relief against the Yankees. Also a skilled hitter by pitcher standards (career batting line of .244/.287/.378), Willis went 3 for 3 with a triple against the Giants in Game 4 of the 2003 NLDS.
Willis was at his best in 2005, when he posted a 2.63 ERA across 236.1 innings and led the majors with seven complete games and five shutouts.
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