Mariners’ Drew Smyly to undergo Tommy John surgery

Mariners left-handed starter Drew Smyly will undergo Tommy John surgery, according to a club announcement. Smyly will miss 12-15 months.

Smyly, who was acquired from the Rays in a four-player deal in mid-January, has not yet pitched this season for Seattle after dealing with elbow issues during spring training. He was expected to be an important middle piece in the M’s rotation behind Felix Hernandez, James Paxton and Hisashi Iwakuma, but instead will spend the season off the mound.

Smyly’s recovery time of 12-15 months makes it possible that he will miss the entire 2018 season, which is his last season under contract before free agency. It is possible that the Mariners non-tender him this winter to prepare for that possibility, giving clubs a chance to sign him to a multi-year deal that would allow him to rehab for 2018.

Smyly, 28, is a veteran of five major-league seasons with Detroit (2012-14) and Tampa Bay (2014-16). He was acquired by Seattle along for Mallex Smith, Ryan Yarbrough and Carlos Vargas on Jan. 11, just hours after the M’s acquired Smith and Shae Simmons from Atlanta for Luiz Gohara and Thomas Burrows.

Smyly posted a 7-12 record and 4.88 ERA in 30 starts with the Rays in 2016.