(WXYZ) - Tigers ace Justin Verlander underwent surgery Thursday morning, according to Detroit Tigers press release.
Verlander suffered an injury to his core muscles during an off-season workout.
Sources say he flew to Philadelphia for the surgery and is expected to start a six-week rehab stint immediately.
"We fully anticipate Justin to participate in spring training and be in a position to compete at the beginning of the 2014 season," said Tigers President, CEO and General Manager, David Dombrowski.
PHOTOS: Justin Verlander's career as a Detroit Tiger: http://bit.ly/1abouJr
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