Fister's injury is a left costochondral strain, which is a ribcage issue.
Last season, Fister went 8-1 with a 1.79 ERA, 0.84 WHIP and 57 strikeouts in 70 1/3 innings after being traded to the Tigers in July.
With Fister on the disabled list, the Tigers used Adam Wilk as a fifth starter, but they lost all three of his starts as he compiled an 8.18 ERA. Duane Below is now the fifth starter until Fister is ready to return.
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