SEATTLE -- Mariners right-hander Hisashi Iwakuma has undergone right shoulder surgery that will keep him from throwing for about five months.
The Mariners announced Iwakuma's surgery on Friday. The shoulder debridement was done Wednesday in Dallas by Dr. Keith Meister. Iwakuma could resume throwing in late February or early March.
Iwakuma had a contract option for the 2018 season but needed to pitch a specific amount of innings for the contract to vest. His injury ended that chance, and he is expected to be a free agent after the season.