Jordan Zimmermann underwent core muscle repair surgery

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The Tigers announced on Thursday that starter Jordan Zimmermann and teammate Christin Stewart both underwent core muscle repair surgery. Both are expected to be ready for spring training.

Zimmermann, 32, had another subpar season, going 7-8 with a 4.52 ERA and a 111/26 K/BB ratio in 131 1/3 innings across 25 starts for the Tigers. In three years since signing with the Tigers as a free agent, he has a 5.24 ERA across 72 starts and one relief appearance. Zimmermann has two years and $50 million remaining on his contract.

Stewart, 24, was a September call-up, playing some outfield. He hit a solid .267/.375/.417 with a pair of homers and 10 RBI in 72 plate appearances.